Canadian Radiation Protection Association Association ...crpa-acrp.org/home/wp-content/uploads/2019/10/CRPA-Bulletin-30-1-web.pdfcal means for protecting all life and the environment

Canadian Radiation Protection AssociationAssociation canadienne de radioprotection

Vol 30 No 1Spring / Printemps 2009

Rapports de l’IRPA 12 àBuenos Aires

Reports from IRPA 12 in Buenos Aires

4-D Organ Motion Effect via Image Guided Radiotherapy

in IMRT Optimization

An introduction to the International Internal Dosimetry Network

An interview with the director of McMaster University’s

Campus Emergency First Response Team

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Canadian Radiation Protection Association /Association canadienne de radioprotection

CRPA is an affi liate of the International Radiation Protection Association. / L’ACRP est membre de l’Association internationale de radioprotection.

President / PrésidentGary Wilson

ph: 902-472-2767email: [email protected]

President Elect / Président désignéDave Tucker

Past President / Président sortantStéphane Jean-François

Secretary / SecrétaireSandu Sonoc

Treasurer / TrésorierWayne Tiefenbach

Directors / Directeurs et directricesRalph Bose, Valerie Ann Phelan, Frank Tourneur, Jeff Sandeman

CRPA Committees / Comités de ACRP

ArchivesTony MacKay (chair / président), Wayne Tiefenbach

Conseil éditorial du Bulletin Editorial Board

Stéphane Jean-François (chief editor / rédacteur en chef), Leona Page (deputy editor / vice-

rédactrice en chef); scientifi c advisors / conseillers scientifi ques: Daniel Picard, Douglas Boreham, Lou

Champagne, Mary Weedmark, Laurie Comeau, Merlin ‘Skeeter’ Seier, Chris Clement, Sandu Sonoc

CommunicationMichèle Légaré-Vézina (chair / présidente),

Lamry Cheriet, Chester Neduzak, Leona Page, Jeff Sandeman, Jodi Ploquin, Greg Zaporozan,

Bulletin Editor / Rédacteur en chef , CRPA/ACRP webmaster, Ralph Bose (BoD liaison), Hoa Ly

Conference / ConférencePauline Jones (chair / présidente),

Mike Grey, Liz Krivonosov, Ralph Bose

CRPA Position Statements /Déclarations publiques de l’ACRP

Stéphane Jean-François (chair / président)

International Liason / Liaison internationale Chris Clement (chair / président), Kevin Bundy,

Michèle Légaré-Vézina, Gary Kramer

Membership / RecrutementEmmy Duran (chair / présidente), Gary Kramer,

Steve Webster

NominationsRay Ilson (chair / président), Geoff Byford, Stéphane Jean-François, Debbie Frattinger

Registration Certifi cation / Enregistrement Certifi cation

Jeff Dovyak (chair / président), Trevor Beniston, Ray Ilson, Sandu Sonoc, Gary Wilson

Rules / RèglementsBliss Tracy (chair / président),

Lysanne Normandeau

Student Affairs / Liaison avec les étudiantsJodi Ploquin (chair / présidente), Leah Shuparski, Michèle Légaré-Vézina, Dave Niven, Sonia Lala

Translation / TraductionRoger Hugron (chair / président), Valerie Phelan,

Colette Tremblay, Stéphane Jean-François, Manon Rouleau.

The Canadian Radiation Protection Associa-tion (CRPA) was incorporated in 1982. The objectives of the association are

• to develop scientifi c knowledge and practi-cal means for protecting all life and the environment from the harmful effects of radiation consistent with the optimum use of radiation for the benefi t of all,

• to further the exchange of scientifi c and technical information relating to the science and practice of radiation protection,

• to encourage research and scientifi c publications dedicated to the science and practice of radiation protection,

• to promote educational opportunities in those disciplines that support the science and practice of radiation protection,

• to assist in the development of professional standards in the discipline of radiation protection; and

• to support relevant activities of other societ-ies, associations, or organizations, both national and international.

The association publishes the Bulletin four times a year and distributes it to all members. Subscription rates for non-members, such as libraries, may be obtained from the secretariat.

Members of the association are drawn from all areas of radiation protection, including hospi-tals, universities, the nuclear power industry, and all levels of government.

Membership is divided into fi ve categories: full members (includes retired members), with all privileges; associate and student mem-bers, with all privileges except voting rights; honourary members, with all privileges; and corporate members. Corporate member-ship is open to organizations with interests in radiation protection. Corporate members are entitled to have their name and address listed in each Bulletin, a complimentary copy of each Bulletin, a copy of the Membership Handbook containing the names and addresses of all CRPA members, reduced booth rental rates at the annual meeting, and reduced advertising rates in the Bulletin.

Application forms are available on the CRPA website or from the secretariat.

Les objectifs de l’Association canadienne de radioprotection, dont les statuts ont été dépo-sés en 1982, sont les suivants:

• Développer les connaissances scientifi ques et les moyens pratiques pour protéger toute forme de vie et l’environnement des effets dangereux des radiations, et ce, d’une manière compatible avec leur utilisation optimale pour le bénéfi ce de tous;

• encourager les échanges d’informations scientifi ques et techniques relevant de la science et de la pratique de la radioprotec-tion;

• encourager la recherche et les publications scientifi ques dédiées à la science et à la pratique de la radioprotection;

• promouvoir les programmes éducationnels dans les disciplines qui soutiennent la science et la pratique de la radioprotection;

• aider à la défi nition des normes profession-nelles concernant la radioprotection, et

• soutenir les activités pertinentes des autres sociétés, associations, organisations natio-nales ou internationales.

Les membres de l’association proviennent de tous les horizons de la radioprotection, y com-pris les hôpitaux, les universités, l’industrie nucléaire génératrice d’électricité et tous les niveaux du gouvernement.

L’association publie le Bulletin quatre fois par an et le fait parvenir à tous les membres. Le prix d’un abonnement pour les non-mem-bres, par exemple une bibliothèque, peut être obtenu auprès du secrétariat.

Les membres sont classés selon cinq caté-gories: membres à part entière (y compris les membres retraités), avec tous les privilèges; membres associés et étudiants, avec tous les privilèges sauf le droit de vote; membres ho-noraires, avec tous les privilèges; et membres corporatifs.

Les membres corporatifs ont droit d’avoir leur nom et leur adresse indiqués dans chaque Bulletin, de recevoir un exemplaire du Bulletin, de recevoir un exemplaire de l’annuaire de l’association contenant les noms et adresses de tous les membres de l’association, d’avoir un kiosque à tarif réduit lors des conférences annuelles, d’avoir un espace publicitaire à tarif réduit dans le Bulletin.

Les formulaires de demande d’adhésion peuvent être obtenus sur le site Web ou auprès du secrétariat.

Prospectus

CRPA / ACRP Bulletin Vol 30 No 1 / 5

The CRPA Bulletin is published quarterly and is distributed to all members of the Association.

Le Bulletin ACRP est publié trimestriellement et distribué à tous les membres de l’Association.

Chief editor / Rédacteur en chef

Stéphane Jean-François

Deputy editor / vice-rédactrice en chef

Leona Page

Design and Production / Montage et production

Michelle Communications

Production team / Équipe de production

Production manager Michelle Boulton English copy editors Geri Rowlat & Michelle Boulton French copy editor Carolyne Roy Translators Caro Gareau de Recio CRPA Translation Committee proofreader Morna Greuel

Advertising / Annonces

Michelle Communicationsph: 306-343-8519

email: [email protected]

Copyright © 2009 CRPA / ACRP

All rights reserved. No part of this publication may be reproduced, transmitted, or stored in a retrieval system in any form or by any means—electonic, mechanical, photocopying, recording, or otherwise—without prior

written consent of the publisher.

For reproduction information, contact Michelle Communications

email: [email protected].

The views expressed in the CRPA Bulletin ACRP are those of the authors and do not represent

the views of the editors or of the association.

Canadian Publications Mail Agreement No. 41574554

Send change of address notices and undeliverable Canadian addresses to

CRPA-ACRP SecretariatPO Box 83

Carleton Place, Ontario K7C 3P3

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Contents/ContenuRegular Columns / Contributions permanentes

7 President’s Message / Message du Président

9 Editor’s Note / Message du rédacteur en chef

10 Contributors

26 Health Physics Corner What is the Expected Field of 3 Lead Blankets?

27 Coin du spécialiste en radioprotection Quel est le champ attendu lorsque la surface aura été protégée par trois couvertures de plomb ?

28 Student Corner / Coin des étudiants Campus Emergency First Response Teams

39 Book Review / Revue de livre Practical Gamma-ray Spectrometry (2nd ed.)

40 Coming Events / Réunions à venir

40 Index to Advertisers

41 CRPA Corporate Members / Membres corporatifs de l’ACRP

Features / Articles

12 IRPA Reports Highlights 12 • by Nicholas Sion13 IRPA 12, Résumé 14 Report on IRPA 12 • by Nicholas Sion24 IRPA 12 Update • by Gary Wilson

30 4-D Organ Motion Effect via Image Guided Radiotherapy in IMRT Optimization Student Paper Contest Runner Up

37 International Internal Dosimetry Network

6 / Vol 30 No 1 CRPA / ACRP Bulletin


President’s Message /Message du Président

This Bulletin is dedicated to providing reports from delegates who attended the International Radiation Protection Association (IRPA 12) Congress held in Buenos Aires, Argentina, in October 2008. No issue can cover all the topics, but I hope the reports found here will give you enough insight into the Buenos Aires congress to convince you to make plans to attend an IRPA congress at some point in your career in radiation protection. The next international congress will be held in Glasgow, Scotland, in 2012.

I would best describe an IRPA congress as a CRPA con-ference “on steroids.” For me, the hardest part of the con-gress was deciding which sessions to attend, as there were five parallel sessions each day. Fortunately, even though it was impossible to attend everything, a brief overview of all of the sessions was given in various plenary sessions, which helped to summarize each of the differently themed topics.

I felt that the time I spent reviewing the poster presen-tations was particularly valuable. The downside was the limited space for the posters. Some were up for only a day or two, so you had to be creative to find the time to get through the aisles and see them; sometimes, that meant missing a session or two of lectures. The upside was that the abstract or other material for some posters was avail-able to take with you, if you didn’t have time to review the whole poster.

When you attend a busy conference in an unfamiliar city, it’s always a challenge to get out and explore that city. I had the good fortune of staying at a hotel some distance from the conference hotel, however, so each day I was able to experience the city during my walk, or subway ride, to the conference site. The other way I experienced the city and the culture of the country was by attending the main conference banquet, which was held at the Sociedad Rural Argentina. A living history of Argentina in song, dance, and action, including horses and battle scenes, was performed in an open-air theatre in the evening. This was followed by a traditional asada, or barbeque. Of course, sampling Argentinian wine was also an important part of the evening. I recommend any Malbec wine from the Mendoza region.

All in all, it was a great opportunity and a great experi-ence. We can all now plan to experience the culture of Montreal at our own CRPA conference this spring, from May 23 to 29. See you there.

Gary Wilson, CRPA(R) President, CRPA

Dans le présent Bulletin, je désire vous transmettre les impressions des délégués qui ont participé au congrès (IRPA12) de l’Association internationale de radioprotection (AIRP), qui s’est tenu à Buenos Aires, en Argentine, en octobre 2008. Tous les aspects de ce rassemblement ne peu-vant être abordés dans un seul numéro, j’espère néanmoins que vous pourrez vous faire une bonne idée du congrès, de façon à envisager de participer à au moins l’un d’entre eux au cours de votre carrière en radioprotection. À ce propos, le prochain congrès aura lieu à Glasgow, en Écosse, en 2012.

La meilleure description d’un congrès de l’AIRP est un congrès de l’ACRP « survolté ». Le plus difficile pour moi a été de choisir les séances auxquelles j’allais participer, car cinq séances avaient lieu en parallèle, tous les jours. Heu-reusement, des séances plénières permettaient de résumer chaque sujet de discussion, ce qui a été très utile pour les séances auxquelles je n’ai pu participer.

L’un des aspects les plus profitables a été de passer en revue les présentations par affiches. La plus grande dif-ficulté a été le manque d’espace pour toutes les affiches, avec pour conséquence que certaines d’entre elles n’ont été affichées que durant une seule journée. Il fallait beaucoup de débrouillardise pour trouver le temps de parcourir les allées des affiches. Quelquefois, il fallait manquer une ou deux séances de présentations orales pour arriver à le faire. Je pense qu’une telle expérience est inhérente à ce genre de congrès. Par ailleurs, certains présentateurs d’affiches distribuaient des résumés écrits ou d’autre matériel que l’on pouvait emporter, ce qui représentait un grand avantage pour les affiches que nous n’avions eu le temps d’examiner en détail.

Quand on se trouve dans une ville qui nous est incon-nue, c’est toujours un défi de sortir l’explorer lorsque le congrès auquel on participe est si prenant. J’ai eu la chance de loger dans un hôtel éloigné du lieu du congrès, de sorte que j’ai pu profiter du trajet quotidien, à pied ou en métro, pour faire connaissance avec la ville. Une autre expérience a été le banquet principal du congrès, qui a eu lieu à la Sociedad Rural Argentina. En soirée, nous avons eu droit à une représentation vivante (chant, danse et jeu) de l’histoire de l’Argentine, où même des chevaux entraient en scène. Présentée dans un théâtre à ciel ouvert, la pièce montrait également des scènes de batailles historiques. La représen-tation était suivie d’un asado (barbecue) traditionnel. Bien sûr, la dégustation des vins argentins n’a pas été étrangère au charme de cette soirée. Je vous recommande à cet effet n’importe quel Malbec de la région de Mendoza.

En résumé, le congrès a été une grande opportunité et une belle expérience. Nous pouvons maintenant planifier de faire l’expérience de la culture montréalaise durant notre propre congrès de l’ACRP, du 23 au 29 mai prochain. On se revoit là-bas !

Gary Wilson, ACRP(E) Président, ACRP


Editor’s Note /Message du rédacteur en chef

It takes two to tango . . . Last October, President Gary Wilson and a CRPA delegation went to Buenos Aires, Argentina, to take a turn on the dance floor with radiation protection specialists from several other countries at a quadren-nial “ball,” otherwise known as the Congress of the International Radiation Protection Association. CRPA is a proud member of IRPA.

This Bulletin offers an account of IRPA 12 from the perspective of the Canadian delegates. Attendees from all over the world grappled with fundamental questions about the nature of the profession and examined the relevance and scientific applicability of radiation protec-tion. Delegates also considered how to apply the discipline to various environments, procedures, and situations—from the day-to-day routine to emergency measures—as well as how to build a regulatory framework to deal with practical issues. Questions about ionizing and non-ionizing radia-tion were equally prevalent. The conference steered into familiar territory with a discussion on the fundamental nature of radiation protection and what it means to be an expert in this field. IRPA 12 delegates even explored radia-tion protection in space with Canadian delegate Nicholas Sion.

This Bulletin also presents the second-place winner of the 2008 student writing competition, an excellent paper by Saberi and Cameron on recent imaging developments that take into account patients’ natural movements such as breathing. Just try holding your breath for that long!

Our contributors continue their excellent work, but we want more! Please do not hesitate to send us your input. We want to start a section on lessons learned in radiation protection. Ready to share your experiences with us? We assure you names will be changed to protect the innocent.

Stéphane Jean-François, Eng., CHP, SSHGD Env. Chief Editor, CRPA Bulletin

Il existe, en anglais, une expression qui dit It takes two to tango (Il faut être deux pour danser le tango)… En octobre dernier, votre président Gary Wilson et une délégation canadienne de l’ACRP ont « dansé » en Argentine avec les spécialistes en radioprotection de plusieurs autres pays lors d’un « bal » qui revient aux quatre ans avec une précision toute olympique, celui du congrès de l’Association inter-nationale de radioprotection (IRPA 12), association dont l’ACRP est membre.

Ce Bulletin vous présente le compte rendu des délégués du Canada. Et bien que l’on réunisse des participants de plusieurs pays, des questions fondamentales sur la profession semblent perdurer. D’abord, on revoit en quoi la radioprotection, en tant que discipline, est pertinente et scientifiquement applicable, puis on cherche à transpo-ser la discipline dans différents milieux, selon différentes procédures et différentes situations, du travail quotidien aux mesures d’urgence et, bien sûr, on cherche à encadrer la pratique par la réglementation. À Buenos Aires, en 2008, on s’est questionné tant sur les radiations ionisantes que sur les radiations non-ionisantes. On semble même être en territoire connu alors que l’on explore la nature fondamentale et la signification de l’expertise en radiopro-tection. IRPA 12 s’est même permis d’explorer la radio-protection dans l’espace avec un représentant du Canada, Nicholas Sion.

Mais revenons sur Terre. Nous vous présentons égale-ment dans ce Bulletin l’excellent article écrit par Saberi et Cameron, qui s’est valu la deuxième place du concours étudiant de 2008. Cet article porte sur les récentes techni-ques d’imagerie pour aider la radiothérapie, qui doit tenir compte des mouvements naturels des patients comme… la respiration. Essayez de retenir votre souffle pour voir !

Finalement, nos collaborateurs continuent leur excel-lent travail, mais nous en demandons plus, chers mem-bres : N’hésitez pas à nous soumettre vos articles. Nous désirons aussi créer une rubrique sur les leçons apprises en radioprotection. Êtes-vous prêts à partager vos expérien-ces ? Nous promettons de changer les noms pour protéger les innocents…

Stéphane Jean-François, Ing., CHP, DESS Env. Rédacteur en chef, Bulletin de l’ACRP.


Contributors

Mehdi Saberi studied radia-tion therapy at Laurentian University in Sudbury, Ontario. In August 2008, he completed his training at the Ottawa Hospital Regional Cancer Centre and graduated with honours with a BSc in radia-tion therapy. He has an interest in radiation therapy physics and medical dosimetry. His research focuses on the impact of organ motion in radiotherapy and intensity modulated radiation therapy (IMRT) optimization.

Mehdi Saberi a étudié la radiothérapie à l’Université Laurentienne de Sudbury, en Ontario. En août 2008, il ter-minait sa formation au Centre de cancérologie de l’Hôpital d’Ottawa et obtenait un baccalauréat en sciences avec spécialisation en radiothérapie. Il s’intéresse à la physique de la radiothérapie ainsi qu’à la dosi-métrie médicale. Ses recherches ciblent l’effet du mouvement des organes en radiothérapie et l’optimisation de la radio-thérapie par intensité modulée (IMRT).

Dianne Cameron received her PhD in medical biophysics in 2000 from the University

of Western Ontario. She was part of the interdisciplinary cancer metastasis team that was responsible for the develop-ment of novel techniques for direct observation of the meta-static process using in vivo vid-eomicroscopy and quantitative stereology. From 2001 to 2003, she worked with the Faculty of Science and Engineering at Laurentian University to develop a new honours bache-lor of science program in radia-tion therapy in collaboration with The Michener Institute for Applied Health Sciences. She joined Laurentian’s Physics Department in 2003, where she teaches courses in medical bio-physics and radiation therapy and continues to direct the BSc program in radiation therapy.

C’est en 2000 que Dianne Cameron a obtenu son doctorat en biophysique de la médecine de l’Université Western Ontario. Elle faisait partie de l’équipe d’observation directe du processus métasta-tique à l’aide de vidéomicrosco-pie in vivo et de la stéréologie quantitative. De 2001 à 2003, elle a œuvré auprès de la Fac-ulté des sciences et du génie à

l’Université Laurentienne pour créer un nouveau programme de baccalauréat en sciences de la radiothérapie en collabora-tion avec l’Institut Michener des sciences appliquées de la santé (Michener Institute for Applied Health Sciences). Elle s’est jointe au département de physique de l’Université Laurentienne en 2003, où elle enseigne en biophysique médicale et en radiothérapie, tout en dirigeant le programme de baccalauréat en sciences de la radiothérapie.

Gary Wilson manages a district-wide medical radiation safety program that encom-passes eight national licences for diagnostic, therapeutic, and research use of nuclear substances, as well as provin-cial regulations for over 100 radiation emitting devices. The program involves approximately 400 workers who use sources of ionizing radiation or radiation emitting devices. Gary has always been actively involved in his professional associa-tions. He served the Canadian Association of Medical Radiation Technologists in various capacities and has been

involved with CRPA since 2000. He is the current CRPA president.

Gary Wilson gère le pro-gramme de radioprotection médicale à l’échelle du district qui comprend huit licences nationales pour l’utilisation de substances nucléaires pour des raisons de diagnostic, de thérapie et de recherche, ainsi que des règlements provinciaux pour plus de 100 appareils d’émission de rayonnements. Le programme implique environ 400 travail-leurs qui utilisent des sources de rayonnement ionisant ou des appareils d’émission de rayonnements. Gary a toujours été activement impliqué dans ses associations profession-nelles. Il a œuvré à plusieurs titres au sein de l’Association canadienne des technologues en radiation médicale, et s’implique dans les activités de l’ACRP depuis 2000. Il est le président actuel de l’ACRP.

Nicholas Sion is a gradu-ate of London University, United Kingdom, and com-pleted postgraduate studies at Birmingham University, United Kingdom. He was employed at


the Ontario Power Generation (OPG) for about 28 years designing radiation monitoring instrumentation and reactor control. His discriminating tritium monitor, stack moni-tor, and C-14 monitor designs are operational at OPG and at Bruce Power. Sion was also a consultant at Atomic Energy of Canada Limited (AECL) for 2½ years on the MDS Nordion Medical Isotope Reactor (MMIR) project.

Nicholas Sion est diplômé de l’Université de Londres, au Royaume-Uni, et a ter-miné ses études supérieures à l’Université de Birmingham, au Royaume-Uni. Il a œuvré auprès de Ontario Power Generation (OPG) pendant environ 28 ans dans la concep-tion d’instruments de surveil-lance des rayonnements et dans le contrôle de réacteurs. Ses conceptions discriminantes d’appareils de surveillance du tritium, de surveillance de faisceau, de surveillance du C-14 sont à l’oeuvre chez l’OPG et chez Bruce Power. Sion a aussi joué le rôle de conseiller auprès de Énergie atomique du Canada limitée (EACL) pendant 2 ans et demie sur le projet de MDS Nordion destiné à la production d’isotopes à des fins médicales (MMIR).

Gary H. Kramer has a BSc in chemistry and a PhD in physical inorganic chemistry from Sussex University, United Kingdom. He moved to Canada in 1975 and spent five years as a post-doc before joining Atomic Energy of Canada Limited’s Chalk River Laboratories. In 1987 he moved to Health

Canada to become head of the Human Monitoring Laboratory (HML). He has established the HML as a centre of excellence for in vivo monitoring and has pursued a vigorous career in research with many journal publications and technical reports to his credit. He is also a founding member and past president of CRPA.

Gary H. Kramer a terminé ses études à la Sussex University (R.-U.) avec un baccalauréat en sciences de la chimie et un doctorat en chimie inorganique physique. Il emménage au Can-ada en 1975, où il passe cinq ans dans un poste post-doctoral avant de se joindre à l’équipe d’Énergie atomique du Canada limitée aux laboratoires de Chalk River. En 1987, il accepte le poste de chef du Laboratoire de surveillance humaine (LSH) auprès de Santé Canada. Il établit le LSH comme centre d’excellence pour l’observation in vivo et poursuit avec vigueur des intérêts de carrière en recherche. En effet, quantité de publications et de rapports techniques lui sont attribués. Gary Kramer est aussi membre fondateur de l’ACRP, dont il est l’ancien président.

Emélie Lamothe is a health physicist with OPG (Ontario Power Generation), respon-sible for software used for the management of radiation hazard and dose data and for dose records. Previously, she worked for AECL, where she held various roles in the areas of research, health physics, and industrial safety.

Emélie Lamothe est spécia-liste en radioprotection auprès de la société Ontario Power Generation (OPG). Elle est responsable des logiciels utilisés dans la gestion des risques d’irradiation et des données de dosage, de même que des dossiers de dosage au sein de l’OPG. Avant de travailler chez l’OPG, elle était employée à l’EACL où elle occupait plu-sieurs postes en recherche, en radioprotection et en sécurité au travail.

Leah Shuparski is a 5th year medical and health physics co-op student at McMaster University. She is slated to grad-uate in May 2009 (yikes!). She is a senior member of McMaster Students’ Union Emergency First Response Team.

Leah Shuparski est étudiante de 5e année du programme d’enseignement coopératif en physique de la médecine et de la santé à l’Université McMaster. Elle prévoit terminer ses études en mai 2009 (déjà !). Elle est mem-bre supérieur de l’équipe Stu-dents’ Union Emergency First Response Team de l’Université McMaster.

Michael Grey is a senior analyst with Candesco Corporation in Toronto, Ontario, and past president of CRPA.

Michael Grey est analyste principal chez Candesco Corpo-ration de Toronto, Ontario, et ancien président de l’ACRP.


REPORTSby Nicholas Sion

The IRPA 12 Congress, held in Buenos Aires, Argentina, in October 2008, was overwhelmed with the highest attendance ever—some 1,300 participants from about 90 countries. These top-level, world-class scientists, including a strong Canadian presence of 10, who gave 14 presentations, enriched the knowledge not only of those attending the congress but also of our profession, in general.

The speeches given during the Open-ing Ceremony by Abel Gonzales (vice-president, IRPA Congress), Ana Maria Bomben (head, Argentine SAR), and Philip Metcalf (president, IRPA) set the theme of the congress: “Towards Global Radiation Protection.” A major concern was voiced—that potentially harmful ionizing radiation should not be used for security purposes. This prompted calls for renewed thinking on the need to share our knowledge and expertise during the current nuclear renaissance.

Other highlights of the congress included the following:

• Tributes to Dr. Dan Beninson Tributes were evoked for his interna-

tional contributions to ICRP 60 and to the IAEA.

• The Sievert Lecture This year’s lecture was given by Dr.

Christian Streffer, who stressed that clustered DNA damage is unique and very difficult to repair as it occurs at high LET. Adaptive response has many biological end points and decreases with age, and it is not observed in either prenatal development or in

Highlights

hyper-radiosensitive individuals. How-ever, it is not recommended as a tool for radiation protection (RP).

• Radiation Protection There has been no change in

UNSCEAR 2000 radon values. Epide-miology at low doses is questionable: is there a threshold? According to the World Health Organization (WHO), a great deal of disease and death (about 13 million deaths worldwide) can be averted by modifying the environment; WHO stressed the need to establish a link between mobile phones and head/neck cancers and recommended restricting the use of mobile phones to those over 15 years of age. Low-dose radiation has produced an adaptive response such that a small priming dose leads to reduced effects from challenge doses (NCRP). ICRP 60 has been replaced by ICRP 103 (2007).

Two factors—an increasing world population that requires more energy and electrical power and a nuclear renaissance—have led to a severe shortage of RP staff worldwide. As of June 2008, there were 439 nuclear operating reactors worldwide. Twenty-five new reactors are under construction in France, and 15 to 20 reactors are to be commissioned in the United States. Even so, the average dose for nuclear energy workers (NEWs) is steadily being reduced.

Overall, radiation protection is becoming part of radiation culture and is disseminated using a harmonized global approach. This trend also involves relevant stakeholder experts, who value the expres-

sions of different perspectives. Standard-ization of dose-rate constants in external dosimetry is essential, however, since these constants vary in different publications by as much as 20:1. In terms of protect-ing the public, the current collective dose matrix models are acceptable.

• Radiation Sources Sources of radiation must be safe-

guarded to avoid their loss through terrorist attack. Thwarting the plots of locally acting terrorists is imperative.

• Occupational Protection Safety culture, specifically, the optimi-

zation of safety, was highlighted in the session on occupational protection. ISOE has databases on nuclear reac-tors and on global occupational dose data; IAEA emphasizes the develop-ment of education and awareness and the protection of pregnant workers. Considering aircrews as radiation workers is advocated, due to their occupational exposures.

Interventional procedures are criti-cal in the medical field. Patient accident data (UNSCEAR 2008) are alarming and demand radiation protection for patients. Medical exposures to radiation for women and their fetuses should be limited and should take into account genetic suscep-tibility. France has developed a “scale rating” for communicating with patients and the public, with an error-reporting system. RP committees should ensure that knowledge is shared and reaches all facilities; as well, these committees should

continued on page 14 . . .


13 au 18 mai 2012. Par ailleurs, l’inten-tion de préparer une proposition pour le congrès de 2016 a été accordée à la ville de Cape Town, en Afrique du Sud.

Les personnes suivantes ont été élues au conseil exécutif : Alfred Hefner (Autriche), Bernard LeGuen (France), Jong Kyung Kim (Corée) et Eduardo Gallego (Espagne). L’assemblée a appuyé les nominations suivantes au conseil exé-cutif : Dick Toohey (États-Unis) à titre de trésorier, Jacques Lochard (France) à titre de cadre supérieur et Dick Griffith (États-Unis) à titre de directeur des relations publiques.

Dans son discours d’ouverture, « Towards Global Radiation Protection », Philip Metcalf (président de l’AIRP) a parlé au sujet du besoin de renforcer la radio-protection sur le plan mondial, du fait que l’utilisation des rayonnements ionisants pour des raisons de sécurité ne devrait pas engendrer de risque inacceptable.

Les présentations au congrès étaient regroupées en trois thèmes principaux : l’épistémologie de la radiation (les effets de l’exposition à la radiation) ; le para-digme de la radioprotection (assurer la sûreté des individus par rapport aux effets sur la santé causés par l’exposition à la radiation) ; et la radioprotection et la sûreté en pratique (l’application et l’utilisation de la radioprotection par les praticiens).

En plus de leur participation à l’as-semblée générale, Kevin Bundy (CCSN) et Nicholas Sion (Intercan Technologies) ont donné des présentations orales et par affiches lors du congrès. Parmi les autres

présentateurs canadiens, on compte Chris Clement (Commission canadienne de sûreté nucléaire), Gary Kramer (Santé Canada), Jan Zielinski (Santé Canada), Jing Chen (Santé Canada), Doug Cham-bers (Senes Consultants) et Ed Weller (Institut de technologie de l’Université de l’Ontario).

Parmi les présentations principales, on compte la conférence de Sievert, présentée par Dr Christian Streffer, professeur à l’Université de Fribourg, qui soulignait les défis et la fascination associés à la recherche biologique en plus de présenter un bref aperçu historique de la radioprotection.

Deux sessions plénières ont eu lieu. La première, sur la radioprotection en pratique, soutenait que l’accident de Tchernobyl a mis en évidence le besoin de mécanismes institutionnels mondiaux sur la radioprotection ce qui a eu pour résul-tat la prolifération d’associations et de comités visant le partage de connaissances et la promotion d’une interaction proche entre les divers organismes de réglementa-tion sur la radiation.

La deuxième session plénière, qui portait sur le paradigme de la radioprotec-tion, discutait de l’intention de créer un modèle conceptuel pour assurer la sécurité de la population. L’atelier se concentrait sur des façons de renforcer la radioprotec-tion à l’échelle mondiale en mettant sur pied un cadre de radioprotection par le biais de l’Agence internationale d’énergie atomique (AIEA) et en élaborant des mécanismes de préparation et de réponse pour la planification en cas d’urgence à l’échelle mondiale.

Pour plus de renseignements sur le congrès ainsi que des photos de ses activités, consultez le lien du congrès IRPA 12 sur la page d’accueil du site de l’AIRP (www.irpa.net).

IRPA 12, RésuméBuenos Aires, 19 au 24 octobre 2008

Le récent congrès (IRPA 12) de l’Associa-tion internationale de la radioprotection (AIRP) qui a eu lieu à Buenos Aires est la rencontre la plus fréquentée de l’AIRP depuis ses débuts. L’activité a attiré 1 300 participants ; 1 500 communications ont été soumises en provenance de 90 pays ; et 250 animateurs ont présenté 38 ateliers spécialisés et cinq ateliers en parallèle.

L’ACRP compte parmi les 48 sociétés nationales représentant 61 pays au sein de l’AIRP. Lors de l’assemblée générale, notre association a été représentée par quatre des 195 délégués ayant droit de vote, dont Kevin Bundy, Lamri Cheriet, Nick Sion, et Gary Wilson.

Dans son rapport présenté au début de l’assemblée, le président a annoncé que l’Organisation internationale du travail (OIT) avait reconnu la radioprotection en tant qu’occupation. En novembre 2008, une ébauche de la définition du terme « expert en radioprotection » a été publiée et se trouve sur le site Internet de l’AIRP (www.irpa.net) ou sur le site de l’OIT (www.ilo.org).

Plusieurs amendements à la consti-tution ont été apportés à l’assemblée générale. On a notamment demandé au conseil exécutif de s’intéresser davantage au congrès et de ne pas se fier au comité organisateur local ou à l’état membre. Cela devrait permettre aux régions plus petites, dont l’effectif est moins élevé, d’accueillir le congrès. Il est intéressant de souligner que l’ACRP a pris la même direction par rap-port à l’établissement de son propre comité organisateur de congrès.

Glasgow a été choisie comme ville hôte pour le prochain congrès, qui aura lieu du


IRPA 12 Highlights. . . continued from page 12

promote close interactions between radiation regulatory bodies. A high level of harmonization and uniformity must be applied in radiation safety.

• Radiation Paradigm The culture of the radiation

paradigm calls for safety first and foremost and, then, ongoing main-tenance of a nation’s capability for radiation protection.

• Radiation Protection in Flights and Space

This session focused on the dose received by aircrews and the galac-tic cosmic radiation that causes cluster DNA damage.

• Decommissioning The final use of a site—will it

become green fields or will it be reused—must be considered. A sys-tematic approach to ALARA is to be followed, guided by the relevant IAEA recommendations.

• IRPA Business The constitution was revised,

with four non-controversial amendments.

• IRPA 13 (2012) After winning the vote over Cape

Town, South Africa, by a margin of 140 to 50, Glasgow, Scotland, was declared the host city of IRPA 13 in 2012.

countries were represented, 1500 papers were submitted, and there were 250 pre-senters. The congress had 38 topical ses-sions and 5 parallel sessions.

This large gathering of top-level, world-class scientists undoubtedly enriched the field of radiation protection, although, naturally, the IRPA staff was overwhelmed by the number of delegates. The situation was compounded by a clock change to Argentina’s summertime on the day many attendees arrived, a change that few of them were aware of.

Details of the congress are described next.

The Business MeetingA change was recommended in the IRPA Constitution (the constitution was written in 1964, and IRPA was officially founded on June 19, 1965). This change had four basic, non-controversial amendments that dealt with:• Reformatting the constitution to make

it gender neutral.• Holding IRPA meetings every four

years (as is done currently), rather than every three years.

• Paying membership fees on January 31, rather than December 31, to avoid the holiday period.

• Transferring some executive duties to the treasurer.

• Deleting the flat-rate fee to allow for flexibility, and increasing personal membership fees from $2.50 To $3.00;

• Adding the clarification that “con-gress” can be regional and/or international.

• Adding that the definition of “coun-try” will be as defined by the United Nations.

• Adding that new IRPA member-states must have a code of ethics that is con-sistent with the IRPA’s.

• Deleting the requirement for two signa-tures on cheques to simplify logistics.

• Revising/substituting the word “audit” in accounting with “review,” as differ-ent countries have different definitions and requirements in conducting audits (e.g., the US. CPA is too restrictive).

• Removing the requirement for IRPA members to submit membership names, as fees are numerically based.

• Assigning responsibility for interna-tional congresses to the IRPA president and executive council; local arrange-ments are to be the responsibility of IRPA’s vice-president.

• Allowing a country to put forward an “expression of intent” to host an inter-national IRPA congress, eight years in advance.

The Opening Ceremony Dr. Abel Gonzales (vice-president, Con-gress Affairs, IRPA) read the welcome speech, which was followed by a presenta-tion by Ana Maria Bomben (SAR, Argen-tine Radiation Protection Association).

Philip Metcalf (president, IRPA) gave the opening address of IRPA 12, the theme of which was “Towards Global Radiation Protection.” The essence of his presenta-tion was twofold:

• Their is a need to strengthen radiation protection worldwide.

• There is a concern about using ion-izing radiation for security purposes; in effect, assurances must be made that radiation used for safety and security will not cause undue harm.

There are 20,000 radiation safety profes-sionals worldwide. In order to achieve a global nuclear-safety regimen, renewed thinking on the need to share our knowl-edge and expertise is required during the current nuclear renaissance.

Report on IRPA 12Buenos Aires, Argentina by Nicholas Sion

IRPA 12 was the most well attended IRPA Congress to date. There were more than 1300 participants, and some 1600 attend-ees in all, including accompanying persons and social participants. In addition, 90




Tributes to Dr. Dan Beninson During the congress, the memory of Dan Beninson was evoked and his internation-al contributions to ICRP 60 and to the IAEA were honoured.

The Sievert Lecture Dr. Christian Streffer, professor at the University of Fribourg, gave the Sievert Lecture. Dr. Streffer highlighted the chal-lenges and fascination of biological re-search and gave a brief historical account of radiation protection:• Radiation was discovered, and hands

were used for experimentation.• The first units of radiation were

created.• The REM unit was defined.• Watson and Crick described the

double helix of the DNA repair mechanism by irradiating the male Drosophila fly to produce a mutant offspring.

• The RAD and GRAY became the cur-rent units.

Regarding Linear No-Threshold (LNT) theory, he noted that solid cancers fitted the linear dose response up to 20 Gy. There is scatter at the lower end, and the radiation effects < 100 mSv are covered within the noise of random cancers. One transferred cell can lead to cancer with 109 cells decades later. Dr. Streffer also noted the following:• DNA double strand breaks have been

detected in very low dose ranges. The DNA repairs to normal in < 2h but it also depends on the genetics of the individual person.

• Clustered DNA damage is unique and very difficult to repair since there is no template to copy from (as in a single strand break). Clustered DNA damage occurs in high LET (linear energy transfer).

• Adaptive response (AR) is seen in mice after irradiation with low doses but var-ies between individuals. - AR is seen with many biological

end points.- LET —Little or no AR occurs at

high LET radiation.

- Genetic disposition—little or no AR is observed in individuals with hyper-radiosensitive syndromes.

- Little or no AR is observed in prenatal development.

- AR decreases with age.- AR is not recommended as a tool

for radiation protection.• AR telomeres are important in stabiliz-

ing chromosomal aberrations.• The lengths of telomeres are crucial in

determining the development of later cancers and the genomic instability that promoted the development of the cancer.

• There is strong evidence between genomic instability and cancer.

• The question is, does genomic instabil-ity occur at low doses?

• 600 billion cells are formed daily in a person.

Dr. Streffer’s parting thought was a quote by Socrates. “Make a decision according to knowledge and not to the number of voices.”

UNSCEAR In his session, Mr. Crick of the United Kingdom stated that the main source of radiation is from natural sources:• At Chernobyl

- Two people died instantly.- Twenty-eight people died from

radiation.- Numerous cases of leukemia and

cataracts followed.- Atmospheric weapons testing con-

tributed 22 mSv.• The effects of exposure

- Between 1 mSv and100 mSv, there is uncertainty, falling within the LNT category.

- Between 100–1000 mSv, there is a linear increase in risk.

- Beyond 1000 mSv, there is a very rapid increase in risk.

• The death of a cell is considered deterministic.

• Cancer is considered stochastic.• Epidemiology at low doses is question-

able; might there be a threshold?

• for radon, there is no change from UNSCEAR 2000 values

• the ERR (excess relative risk) at 100Bq/m3 = 0.16, and this is found in smokers

World Health OrganizationDr. Marie Neire spoke on the levels and effects of radiation.

• How much disease could be prevented by modifying the environment? Some 13 million deaths could be averted worldwide.

• Non-ionizing radiation —there are numerous studies on electromagnetic fields (EMF).

• The earth’s magnetic field is 0.03-0.07 Tesla (T).

• The MRI is > 2 T.• Acute effects of static fields, > 100 μT,

are in moving blood around or in body movements.

• Low frequency fields are > 0–100 kHz.• Long-term effects—childhood leukemia,

breast cancer, adult brain cancer.• There is a need to establish a link

between mobile phones and head/neck cancers. Independent studies have been conducted by Interphone, Cosmos, and a third group. It is recommended that the use of mobile phones be restricted to those over 15 years of age.

• UV radiation—there are 200,000 cases worldwide, which result in 4,500 deaths from melanoma that could be avoided.

National Council on Radiation Protection & Measurements (NCRP)The NCRP has reiterated the limits on the precision of epidemiology and on data at low radiation doses. Low-dose radiation has produced radio adaptive response (RAD), such that a small priming dose of ≤ 50 mGy leads to reduced effects from challenge doses.

Recent Achievements in External Dosimetry There are active and passive personal do-simeters and neutron dosimeters. OSLs (optical stimulation luminescences) are better than Thermoluminescent Dosimetry (TLD), as they do not require heating.


Report on IRPA 12. . . continued from page 14


Dose Rate Constants Different publications use different num-bers, probably because the measurements are anisotropic, that is, measured from different directions. An example for Am-241 shows the following:

• 4.28 x 10-15 Sv. m-2 . h-1 .Bq-1 • 5.96 x 10-15 Sv. m-2 . h-1 .Bq-1 • 5.67 x 10-15 Sv. m-2 . h-1 .Bq-1 • 50.38 x 10-15 Sv. m-2 . h-1 .Bq-1 • 83.56 x 10-15 Sv. m-2 . h-1 .Bq-1 These numbers vary by 20:1, using the same units. So which numbers should be used? Clearly, this issue calls for standard-ization.

Protection of the Public and the EnvironmentThis session focused on concerns about radioactive elements finding their way into the environment, such as uranium in water from the Ezeiza atomic site in Argentina. Numbers given to illustrate this concern were the following:

• Ground water in Israel, for Radon-226 < 0.02 Bq/L.

• Australian guidelines are 1 mSv/y.

• Public acceptance is 0.1mSv/y.The current collective dose matrix models are acceptable, but the individual dose is not possible due to food distribution.

Occupational ProtectionThis session highlighted the safety culture, the monitoring tools and techniques, and the motivation for and benefits of occu-pational protection. As well, it was noted that regulatory bodies and international organizations are now taking proactive roles in the area; that optimization of safety is imperative; and that the study of the risk of carcinogens will continue as human longevity increases.

UNSCEARAccording to an overview of the re-evaluation of occupational protection• 13 million workers are exposed to

natural sources of radiation, of whom

88% are in mining, 10% work with radon, and 2% are aircrew.

• 10 million workers are exposed to artificial sources of radiation, of which 80% is medical, 9% is industrial, and 4% is military activities.

ISOE (Information System on Occupational Exposure)The databases of the organization known as ISOE contain compiled data on 471 nuclear reactors (395 of which are op-erating and 76 of which are shutdown), including global occupational dose data, dose reduction, and operating experience. ISOE is able to exchange any of this infor-mation. Its website is found at www. Isoe-network.net.

The International Atomic Energy Agency (IAEA)IAEA emphasizes the development of education and awareness on the holistic approach to radiation, exposure to natural radiation, and protection of pregnant workers.

Safety of Radiation SourcesThis session dealt with the possibility of plots against radiation sources by locally acting terrorists. The security evaluation methodology (developed by Sandia) in-cluded the following:• Facility characterization.• Interviews with all staff, including

cleaners.• Target identification, e.g., hospitals.The following was also noted: • The use of self-protecting radioac-

tive sources is advocated from fixed machines, according to IAEA category I, II, and III.

• The inventory of sources in Russia is from 0.01 – 1 TBq (Am-241 sources are used mainly as tools).

• Protection depends on the extent of public concern; therefore, close co-operation is needed between institutions.

• In Nigeria, because a number of sources have been lost, all expired sources are now shipped back to their point of origin.

Canadian Presence at IRPA 12Canada was represented by four delegates (a reflection of the size of the CRPA mem-bership): Gary Wilson, Nicholas Sion, Kevin Bundy, and Lamri Cheriet. All of them participated in the Business Meeting and the voting, but Gary was particularly active.

Chris Clement (CNSC) presented his pa-per “Ionizing Radiation Protection Regula-tion in Canada,” in which he noted that the nuclear industry in Canada is most mature in uranium mining, particularly in the production and export of radioisotopes, fuel refining, and fabrication. Chris also outlined the roles of the FPTRPC (Federal/Provincial/Territorial Radiation Protection Committee) and those of the CNSC in regulating power reactors in nuclear gener-ating stations and in research reactors.

Kevin Bundy’s (CNSC) oral and poster presentation was titled “The Regulatory Assessment of the Use, Subsequent Dose


Canadian delegates: Kevin Bundy, Gary Wilson, Lamri Cheriet, and Nicholas Sion.

Chris Clement (CNSC) presented his paper “Ionizing Radiation Protection Regulation in Canada.”


and Health Risks Posed by Tritium in Canada.” As well as providing an overview of the use of, and doses due to, tritium in Canada, he noted that a study by the United Kingdom Advisory Group on Ion-izing Radiation (AGIR) had reviewed the relative biological effectiveness (RBE) and subsequently recommended that the cur-rent ICRP WR weighting factor for tritium be raised to 2 for routine RP assessments for tritium.

Nicholas Sion’s (Intercan Technolo-gies) oral and poster presentation, “The Radiation Protection of Astronauts on Prolonged Space Missions,” reflected the severity of galactic cosmic radiation (GCR) in causing cluster DNA damage and its higher LET (linear energy transfer), bio-medical effects and countermeasures, risk assessments, and requirements for reduc-ing uncertainties, some of which are listed in NCRP 153.

Lamri Cheriet (CHUS) attended the daily refresher courses that were offered by IRPA 12.

Gary Kramer (Health Canada) was on the Executive Council and so attended various committee meetings. However, he also pre-sented papers on the characterization of radiation exposure (where new estimates for human lung dimensions were investi-gated using phantoms), on occupational protection, and on the Canadian National Dosimetry Intercomparison Program, in which the CNSC has instituted a new requirement for licensees that will be ad-ministered by Health Canada.

Jan Zielinski (Health Canada) proffered several papers:• “The Risk of Occupational Exposure

to Ionizing Radiation among Medi-cal Workers” dealt with chronic low dose radiation. Data indicated higher thyroid cancer among medical workers

• In a paper on circulatory disease mortality, the radiation effects due to a dose of ∼40 Gy were considered deterministic. When the ERR (excess relative risk) was adjusted by stratifica-tion for age, job type, gender, etc., it showed a significant dose response for men (ERR/Sv of 1.22) and for women (ERR/Sv of 7.37).

• A paper on the Canadian Dose Registry included a database for occupational exposures for 600,000 nuclear, indus-trial, medical, and dental workers.

• For the paper “Mapping Residen-tial Radon in the World,” data was collected, mapped, and put on the website with a Google Earth version.

• “The WHO International Radon Project” paper outlined the goals of the project—to impart greater aware-ness and provide the tools for radon control.

Jing Chen (Health Canada) presented two papers:• “The Uranium GI Absorption Coef-

ficient for Young Children” noted that the absorption fraction is important

in assessments for uranium burdens in the GI tract. For three-month-old infants, it was 0.256, which is six times the value used in ICRP

• The second paper, “The Geographic Analysis for Indoor Radon and Soil Radon Distribution in Ottawa,” provides a useful tool for identifying radon-prone areas.

Doug Chambers (Senes Consultants) gave an overview of his paper “Representative Risk Assessments Conducted for Sites with Enhanced Radioactivity,” for which numerous ecological risk assessments were carried out. Doug also co-authored the paper “Mapping Residential Radon in the World” with Jan Zielinski (Health Canada).

Ed Weller’s (University of Ontario In-stitute of Technology [UOIT]) oral and poster presentation “Canadian Space Agency Discipline Working Group for Space Dosimetry and Radiation Science” reflected the need for instrumentation for the space environment to withstand the deleterious effects of radiation. It also out-lined the three core activities of the agency in conjunction with Defence Research and Development Canada, the Royal Military College of Canada, and the Faculty of En-gineering, University of Regina.

PLENARY SESSION: Radiation Safety in Practice After the Chernobyl accident, the need for global institutional mechanisms on nuclear radiation safety became apparent and resulted in the proliferation of associa-tions and committees for the purpose of sharing knowledge, to ensure the informa-tion reached all facilities, and to promote close interactions between the radiation regulatory bodies. The stakeholders must remain vigilant.

Harmonization of Standards

A high level of harmonization and unifor-mity must be applied in radiation safety. This is crucial because medical exposure is increasing, mainly in CT scans, in in-tervention procedures, and in imaging modalities. Of particular concern were the following:

• As dose limits do not seem to apply to medical exposures, reference levels are needed for optimization.

• The challenges of medical exposures include—setting different limits for women and fetuses; considering the


Kevin Bundy (CNSC) gave an oral and poster presentation titled, “The Regulatory Assessment of the Use, Subsequent Dose and Health Risks Posed by Tritium in Canada.”

Nicholas Sion’s (Intercan Technologies) gave an oral and poster presentation titled, “The Radiation Protection of Astronauts on Prolonged Space Missions.”


genetic susceptibility when applying dose to the eye lens; considering occu-pational exposures for aircrew; and decommissioning older nuclear facili-ties built when concern for decommis-sioning was less.

• The evolution of RP is a continuum of incremental enhancement, with increasing transparency, which requires a balance between harmonization and trust in institutions.

• The challenges are in emergency exposures that require an integrated approach and in the economics of decision-making.

PLENARY SESSION: Radiation Protection ParadigmThe intent of the conceptual model is to keep people safe, and the theme of IRPA 12 was to strengthen RP worldwide. To achieve these goals, three factors are involved—developing an RP framework (IAEA); developing methods and culture; and emergency planning preparedness and response.

Developing an RP framework (IAEA)

• Develop a culture of safety first and foremost.

• Institute regulatory effectiveness and independence.

• Avoid complacency and non-vigilance.• Develop and maintain a national capa-

bility for RP.

Developing methods and culture

• the scope of RP was defined in ICRP 60; it was replaced by ICRP 103 in 2007.

• the protection of the public, the environment, and non-humans (not essential in developing countries) and the need to share understanding are crucial.

• Occupational protection must be insti-tuted, yet interventional procedures are critical in the medical field. RP for patients is alarming, according to UNSCEAR 2008 data, with numer-ous accidents. France has developed a “scale rating” for communicating

with patients and the public. An error-reporting system is required and should be harmonized and graded.

Emergency planning preparedness and response

• Efforts to develop national prepared-ness worldwide are encouraged.

• There is a new focus on malicious acts and on mass casualties that can over-whelm the system.

• A new focus on recovery is also being encouraged.

• Legal issues involved in transporting contaminated patients to assisting countries must be resolved.

• States must recognize they may need assistance; the donor/recipient mental-ity must be eliminated.

Radiation Protection in Nuclear Reactors

In his presentation, Dominique Miniere (vice-president, EDF, France), noted that, in France, about 80% of power generation is from 58 nuclear reactors, which produce 50 gm/kWh of CO2 as compared with 400 gm/kWh of CO2 in Europe. Another 25 reactors are under construction.

World inventory for oil is 40 years; for natural gas, it is 70 years.

France’s EDF has managed to reduce the collective dose from 2.44 man-sieverts (mSv) in 1991 to 0.63 mSv in 2007. Fol-lowing are some statistics from the EDF labour force:

• In 1992, 1200 workers had an annual dose of 20 mSv.

• In 2001, 92 workers had a dose of 18 mSv.

• In 2007, the dose was reduced to just 2 mSv.

In comparison, in Japan, the average dose to nuclear station workers is 1 mSv/y; to the public, it is 1 μSv/y.

According to Duke Energy, United States, the current era of resurgence of nuclear power in the United States is characterized by an emphasis on radiation safety. There are 104 operating nuclear power plants in the United States, with consideration be-

ing given to 32 new reactors; five designs are under review by the NRC; and 15 to 20 new reactors are to be commissioned by 2020.

According to E-On Kernkraft of Germany, 21 nuclear power plants are operating in Germany, with an installed capacity of 11 GW. E-On has a staff of 3300, including 20 full-time RP personnel. The organiza-tion has had a problem recruiting RP staff given the severe shortage of RP workers.

Philippe Bosquet (deputy vice-president, Safety, Health and Security, AREVA, France) noted that, at AREVA, there is a group restraint to maintain the dose at < 20 mSv/man/y. In comparison, in the United States, the dose is ∼ 50 mSv/y, 100 mSv over 5 years. At AREVA, the average dose has been reduced from 1.45 mSv (2002) to 1.19 (2007).

Argentina’s vision is to build two high-temperature reactors for power generation and for the production of hydrogen. A regional integration with Brazil is contem-plated. Apparently, a generation gap exists between old and new recruits into RP due to nuclear quiescence. Currently, the em-phasis is on radiological and environmen-tal protection, rather than environmental safety programs.

In Brazil, uranium mining capacity is 400 tons/y (2008); the country’s target is 800 tons/y by 2011.

Dominique Miniere and Bernard Le Guen (EDF, France) discussed RP optimization for the EPR (European Pressurized Reac-tor). The intent is to place the EPR at 0.39 man-Sv/y, below the reference collective dose of 0.44 man-Sv/y. The methods to be adopted are optimization of the collec-tive dose by considering the source terms of the steam generators, the primary heat transport system, thermal insulation, the exposure time, reactor building accessibil-ity, and fuel evacuation.

Trends in Radiation ProtectionRadiation protection has been a key focus of both the industry and the regulatory authorities. All exposures were to the ALARA standard, which has successfully reduced exposures—occupational expo-sures of nuclear plant workers dropped from 1.8 man-Sv to 0.9 man-Sv.

By 2050, it is estimated that



• The world’s population will increase by 50%.

• Energy demand will increase by 100%.

• Electricity demand will increase by 150%.

Hence, greenhouse gases, mainly CO2 , must be reduced by a factor of 4. In June 2008, there were 439 operating nuclear reactors. By 2050, it is estimated there will be from 600 (low estimate) to 1400 reac-tors (high estimate).

Recommendations and Future RP Challenges • Make RP part of the radiation culture

(EDF).

• Require more commitment from the RP community, rather than increasing the statutory framework (EDF).

• Institute skills’ renewal and succession planning (EDF).

• Harmonize the global approach to RP.

• Establish a radiological RP system that is integral to the educational system (Duke Energy).

• Switch from collective to individual dose management (Duke Energy).

• Develop a two-year course in RP for high-school graduates, after which they could proceed to higher academic levels (Duke Energy).

• Increase the understanding of radia-tion health effects—from epidemiol-ogy to cellular and molecular biology (Duke Energy).

Radiation Protection in Flights and Space Several of the presentations in this session highlighted the types of radiation in the earth’s atmosphere, in Low Earth Orbit, and in what is beyond the Van Allen Belts. The dose rate at sea level, at the top of the Himalayas, and at a height of 15 km can be 0.03 micro Sv/h, 1 μSv/h, and 10 μSv/h, respectively (ICRP 103). Given these dose rates, it is recommended that airline crews be treated as radiation work-ers and that dose measurements be made in commercial airlines.

For outer space, operational RP should be instituted for astronauts. For prolonged missions, a special RP program should be implemented (N. Sion, Canada). Measure-

ments aboard the ISS (International Space Station), using Pille dosimeters, have pro-vided high-resolution data (T. Pazmandi, Hungary).

DecommissioningWhen a facility is decommissioned, con-sideration must be given to the final use of the site. That is, will it be green fields or will the land be reused? IAEA has many recommendations that can be ap-plied, mainly concerning the systematic approach to ALARA. Sharing of experi-ence is crucial. The operative keyword in decommissioning nuclear facilities is characterization. Examples of decommis-sioning and the approaches taken and/or challenges that had to be overcome include the following:

Bugey-1

• A radiological inventory was established.

• Operations were planned.• Expected releases were estimated.• the long-distance flow of neutrons was

measured (biasing method).• Amounts of tritium in the soil were

measured.

DR2 Experimental Reactor

• Contamination was controlled by dry cutting and chopping, using a depres-surized tent and separate entrances for personnel.

• Surveillance was done through air monitoring, routine smear tests, using dosimeters, and checking for personnel contamination upon exiting the area.

Reactor at Tuwaitha, Iraq

• the challenges that had to be overcome included—lack of decommissioning expertise; lack of waste storage; the need to develop regulatory competence and interfaces; and unsafe structures.

• Different weighting factors were applied.

• Strong co-operation with IAEA was mandated.

Russian sites (for nuclear submarines)

• Close co-operation with Norway was required to find suitable storage sites at Andreeva Bay.

• the program developed from support to co-operation.

Stakeholder EngagementAccording to Tony Bandle (SRP [Society for Radiological Protection], U.K.), en-gaging RP stakeholders such as doctors, artisans, and ecologists is appropriate because they represent the distillation of a huge amount of real-life experience. Their expertise is the major justification for such engagement.

The principles of stakeholder engagement are openness and transparency, involve-ment of relevant stakeholder experts, and respect and value for the expressions of different perspectives.

Bandle’s parting thought was, “No pro-fessional, however expert they may be, should be an island.”

Jacques Repussard (IRSN [Institut de Radioprotection et de Surete Nucleaire], France), noted that as of 2006, a stake-holder committee is required for each nuclear plant in France. Each committee must work to ensure public trust by• promoting understanding of and tak-

ing leadership on issues,• implementing and striving for cultural

change,• investing in education, and• striving for world-class excellence.In challenging times, the best insurance is having a body that can interact with the public in a positive way. Without trust, it is not possible to lead. Culture is built by experience and that, in turn, builds values.

The IRSN website is at www.irsn.org.

Awards• Professor Christian Streffer received

the 2008 Sievert Award.• Dr. K. Sankaranarayanan received the

2008 Gold Medal from the Swedish Academy of Science.

• Dr. Abel Gonzales received the 2008 Marie Curie Prize, as well as accolades for his contributions to IRPA 12.

• Dr. Ana Maria Bomben, Dr. Eduardo Gallego, and others received awards for their tireless efforts in organizing IRPA 12.

IRPA 13 (2012) Glasgow, Scotland, and Cape Town, South Africa, vied to be the host city of IRPA 13 in 2012. Glasgow won the vote 140 to 50.


The full flavour of the General Assembly is hard to capture in words. Overall, it was a very interesting meeting, and it made me aware of all the IRPA business that is conducted throughout the year. My experience is likely similar to the average CRPA member who may not realize all the volunteer hours put in by people on the association’s various committees or how much time Board members spend dealing with the many issues and questions that pass our way. I have summarized my view of the General Assembly here, but much more information is available on the IRPA website (www.irpa.net).

Canada had 4 voting delegates out of the 195 delegates present at the General Assembly. The team representing the CRPA consisted of Kevin Bundy, Lamri Cheriet, Nick Sion, and Gary Wilson. Philip Metcalf, IRPA president, opened the assembly by noting that the IRPA was comprised of 48 national societies, representing 61 countries. (The numbers differ because some societies represent several countries.) The newest members welcomed at this meeting were Malaysia, Bulgaria, and Columbia; Algeria is no longer a member.

Treasurer’s ReportThe treasurer’s report was a brief overview, as the specific details of the report are available on the IRPA website. Basically, the highlights presented to the delegates acknowledged that the balance of the Montreal IRPA Support Fund has been transferred to the IRPA accounts. This money, along with other dedicated funds, is used to help people from develop-ing countries attend IRPA congresses. Approximately 27 people from 15 coun-tries were attending IRPA 12 on sponsor-ships. Overall, the budget is healthy, with

IRPA 12 UPDATEThe General Assembly by Gary Wilson

75% of the operating income coming from member-state dues. The treasurer proposed that personal dues be increased from $2.50 to $3.00 a year and that each congress should be expected to generate $50,000 to support the operating budget.

Revisions to the ConstitutionSeveral revisions to the constitution were brought to the assembly and passed by the delegates.

First, the Executive Council will take a more vested interest in each congress and not rely solely on the local organizing committee or member-state; the goal is to enable those areas with smaller member-ships to host a congress. Interestingly, the CRPA has taken the same direction with the establishment of its Conference Com-mittee. This committee has already been able to help Edmonton, which has a small number of CRPA members in the local vicinity, to host CRPA 2010.

Second, advisers will be permitted on the IRPA Executive Council if they are required. This will enable the coun-cil to fill any gaps in representation it may have. A motion to require regional representation on the Executive Coun-cil was defeated. The following people were elected to the Executive Council: Alfred Hefner (Austria), Bernard LeGuen (France), Jong Kyung Kim (Korea), and Eduardo Gallego (Spain). The following Executive Council appointments were endorsed by the assembly: Dick Toohey (United States) as treasurer; Jacques Lochard (France) as executive officer; and Dick Griffith (United States) as publica-tions director.

The final revision was in the bidding process to host a congress: rather than having to present a full bid, a city may now simply express an intent to host a

congress. The general assembly will rank the cities that have expressed their intent to host a certain congress, and the top-ranked city will then prepare and submit a bid to the Executive Council for approval. If its bid meets the criteria, the city would host the event. At this congress, which was operating under the old system, Glasgow was selected to host the next congress from May 13–18, 2012. Cape Town, South Africa, was asked to prepare a bid for the following congress in 2016.

Radiation ProtectionIn the report he presented at the start of the assembly, IRPA president Philip Metcalf announced that the International Labour Organization (ILO) had recog-nized radiation protection as an occupa-tion. As a result, the IRPA has prepared a definition of the term “radiation protec-tion expert.”

IRPA Definition of Radiation Protection Expert (RPE)

(A) “Radiation Protection” is that science and art devoted to the anticipation, recognition, evaluation, and control of radiation hazards that may cause impaired health and well-being, or injury among workers, patients, the public, or harm to the environment.

(B) “Radiation Protection Expert (RPE)” is a person:

• having education and/or experi-ence equivalent to a graduate or master’s degree from an accredited college or university in radiation protection, radiation safety, biology, chemistry, engineering, physics, or a closely related physical or biologi-cal science, and

• who has acquired competence in radiation protection, by virtue of


special studies, training, and practi-cal experience. Such special studies and training must have been sufficient in the above sciences to provide the understanding, ability, and competency to

(1) anticipate and recognize the interactions of radiation with matter and to understand the effects of radiation on people, animals, and the environment

(2) evaluate, on the basis of train-ing and experience and with the aid of quantitative measurement techniques, the magnitude of radiological factors in terms of their ability to impair human health and well-being and dam-age the environment

(3) develop and implement, on the basis of training and experi-ence, methods to prevent, eliminate, control, or reduce radiation exposure to workers, patients, the public, and the environment.

(C) In most countries the competence of radiation protection experts needs to be recognized by the competent authority in order for these profession-als to be eligible to undertake certain defined radiation protection responsi-bilities. The process of recognition may involve formal certification, accredita-tion, registration, etc.

ILO Draft Definition of Environmental and Occupational Health and Hygiene ProfessionalsThe ILO’s definition of occupational health and hygiene professionals now includes Radiation Protection Expert as one of those occupations. In November 2008, the ILO published a draft defini-tion, which is included below. The defini-tion can also be found on either the IRPA website or the ILO website (www.ilo.org).

Lead statement

Environmental and occupational health and hygiene professionals evaluate work and other environments and develop and implement programs to monitor environ-mental health and occupational health and safety, to ensure safe and healthy

working conditions, and to prevent disease or injury caused by chemical, physical, radiological, and biological agents or ergonomic factors.

Task statement

Tasks include:(a) developing, implementing, and

reviewing programs and policies to promote environmental health and occupational health and safety

(b) preparing and implementing plans and strategies for the safe, economic, and suitable dis-posal of commercial, indus-trial, medical, and household wastes

(c) implementing prevention programs and strategies for communicable diseases, food safety, waste water treatment and disposal systems, recre-ation and domestic water quality, contaminated and hazardous substances

(d) identifying hazards, and assessing and controlling risks in the environment and workplace and advising on compliance with relevant law and regulations

(e) developing, implementing, and moni-toring programs to minimize workplace and environmental pollution involv-ing chemical, physical, and biological hazards

(f) prescribing methods to prevent, elimi-nate, control, or reduce the exposure of workers, patients, the public, and/or the environment to radiological and other hazards

(g) promoting ergonomic principles within the workplace, such as match-ing furniture, equipment, and work activities to the needs of employees

(h) providing education, information, training, and advice to persons at all levels on aspects of occupational hygiene and environmental health

(i) recording and investigating injuries and equipment damage, and reporting safety performance

(j) coordinating arrangements for the compensation, rehabilitation, and return to work of injured workers.

Included occupations

Examples of the occupations classified here: Environmental Health Officer, Occupational Health and Safety Adviser, Occupational Hygienist, and Radiation Protection Expert.

Themes of the CongressPresentations at the congress were divided into three main themes: the epistemology of radiation (effects of radiation exposure); the radiation-protection paradigm (keep-ing people safe from the health effects of radiation exposure); and radiation protection and safety in practice (applica-tion and use of radiation protection by practitioners). For photos of the various events, visit the IRPA 12 link on the IRPA homepage.

Top, a typical Agentine Barbecue and, below, members of the Canadian delegation enjoying their dinner.


Health Physics Corner

by Emélie Lamothe, Health Physicist

Answer

What is the Expected Field of 3 Lead Blankets?

A few months ago, I sat down to esti-mate how much snow I had to shovel in December. Based on the length and width of my driveway, the depth of the snow, and the specific density of snow, I calculated roughly 2 metric tons. I know that a blanket of snow is a good insulator when winter camping, which turned my thoughts to lead blankets.

Last Issue’s Question

In order to shield work on the reactor face, lead blankets, with each blanket equivalent to ¼-inch solid lead, are to be hung. The outage activity trans-port monitoring gives the following major field contributions:

Co-60 (average 1.25 MeV) – 75%

Nb-95 (0.776 MeV) – 18%

Zr-95 (0.756 MeV) – 7%

If the initial field is 200 mrem/h, what is the expected field after the face is shielded with three lead blankets? What would it be if four blankets were used?

The effectiveness of gamma-ray shielding is often described in terms of the half-value layer (HVL), which is the thickness of absorber required to reduce the gamma radiation to half its former intensity.

The first step is to determine the averaged weighted energy:

averaged weighted energy =

where En is the average energy of radionu-clide n, and Cn is the percentage contribu-tion from radionuclide n.

The mix of field contributions noted above has an averaged weighted energy of:

0.75 x 1.25 (Co-60) + 0.18 x 0.776 (Nb-19) + 0.07 x 0.756 (Zr-95) = 1.13 MeV

The HVL of lead at 1.1 MeV is about 0.8. Assuming no buildup, 3 lead blankets are roughly equivalent to

and thus

Therefore, for 3 lead blankets, the field will be decreased by 20.79 = 1.729 and be about 115 mrem/h (1.15 mSv/h). Repeating this calculation for 4 lead blankets, the estimated field is 22 mrem/h (0.22 mSv/h).

A scientist at a pharmaceutical research centre laboratory was using a tritiation device, a device that allows tritium gas to be adsorbed on uranium beds at room temperature. While loading the beds with tritium gas, the scientist accidentally dropped a pressurized tritium bottle on the floor. Unaware that the valve was bro-ken and 3.7 TBq of tritium was being dif-fused in the room, the scientist remained there for 10 minutes before connecting the bottle to the manifold and realizing there was no pressure left in the bottle! Oops . . .

What is the maximum dose the scien-tist could have received in the lab? What is the maximum potential dose at the research centre’s boundary, roughly 1 km from the exhaust?

This laboratory meets the company’s 12 air changes standards. Corporate poli-cies set a limit of 5 mSv of dose equivalent

for an incidental release. How many air changes per hour will be required to achieve this limit?

Some data: • Laboratory size: 15 m x 10 m x 3 m

• From ICRP Publication 71: breathing rate for an adult is 22.2 m3 per day

• From US EPA Comply Source Code: the atmospheric diffusion factor at 1 km (X/Q) is roughly 1 E-04 s/m3

• From NRC Regulatory Guide 1.109: Dose Conversion Factor for inhaling, including skin absorption (D/I), is 4.05 E-02 Sv/GBq

• Exposure time (T): 10 minutes

Have fun! Remember, this column’s for you. Send me your answers and sug-gestions for future issues to the CRPA Secretariat or [email protected].

This Issue’s Question


Coin du spécialiste en radioprotection

par Emélie Lamothe, spécialiste en radioprotection

Réponse

Quel est le champ attendu lorsque la surface aura été protégée par trois couvertures de plomb ?

L’efficacité de la protection contre le rayonnement gamma est souvent décrite en termes de couche de demi-atténuation (CDA), ce qui correspond à l’épaisseur de l’absorbant nécessaire pour la réduction de rayonnement gamma à la moitié de son intensité originale.

La première étape consiste à déterminer l’énergie moyenne pondérée :

Énergie moyenne pondérée =

où En représente l’énergie moyenne du radionucléide n, et Cn représente la contri-bution en pourcentage du radionucléide n.

Le mélange de contributions dans le champ, notées ci-dessous, comporte une énergie moyenne pondérée de :

0,75 x 1,25 (Co-60) + 0,18 x 0,776 (Nb-19)? + 0,07 x 0,756 (Zr-95) = 1,13 MeV

La CDA de plomb 1,1 MeV est d’environ 0,8. En supposant qu’il n’y avait pas d’ac-cumulation, trois couvertures de plomb seraient environ équivalentes à

and thus

Ainsi, pour trois couvertures de plomb, le champ serait diminué par 20,79 = 1,729 et serait d’environ 115 mrem/h (1,15 mSv/h). Si l’on répète le calcul pour qua-tre couvertures de plomb, le champ estimé serait de 22 mrem/h (0,22 mSv/h).

Il y a quelques mois, je me suis assise pour estimer combien de neige j’avais eu à pelleter en décembre. En fonction de la longueur et de la largeur de mon entrée de cour, de l’épaisseur de la neige et de sa densité spécifique, j’ai calculé que j’avais pelleté environ deux tonnes métriques de neige. Consciente qu’une couverture de neige constitue un isolant efficace pen-dant le camping en hiver, je me suis mise à penser aux couvertures de plomb...

Question du numéroprécédent

Pour protéger le travail de la surface d’un réacteur, des couvertures de plomb, dont chacune équivaut à ¼ pouce de plomb massif, doivent être accrochées. Le suivi de près du trans-port des activités d’arrêt de tranche donne les contributions majeures suivantes :

Co-60 (moyenne 1,25 MeV) – 75 %

Nb-95 (0,776 MeV) – 18 %

Zr-95 (0,756 MeV) – 7 %

Si le champ original est de 200 mrem/h, quel est le champ attendu lorsque la surface aura été protégée par trois couvertures de plomb ? Et si l’on utilisait quatre couvertures ?

Question du présent numéro

Le chercheur du laboratoire d’un centre de recherche utilise un appareil de tritia-tion, un appareil permettant l’adsorption du tritium gazeux, sur les couches d’ura-nium à température ambiante. Ne sachant pas que la valve est brisée et que 3,7 TBq de tritium se dispersent dans la salle, le chercheur demeure dans la pièce pendant dix minutes avant de brancher la bouteille au collecteur et de se rendre compte que celle-ci n’a plus de pression ! Oops ! Quelle est la dose maximale que le chercheur pourrait avoir reçue dans le laboratoire ? Quelle est la dose maximale potentielle aux frontières du centre de recherche, situées à environ un kilomètre de la fuite ?

Ce laboratoire respecte les douze normes de changement d’air de l’entreprise. Les politiques d’entreprise fixent une limite de 5 mSv d’équivalence de dose pour une fuite accidentelle. Com-bien de changements d’air à l’heure seront nécessaires pour atteindre cette limite ?

Quelques données : • Taille du laboratoire : 15 m x 10 m x 3 m • Selon la publication 71 de l’ICRP : le

taux de respiration d’un adulte est de 22,2 m3 par jour.

• Selon le code de conformité à la source de l’EPA des États-Unis (US EPA Comply Source Code) : le facteur de diffusion atmosphérique à 1 km est d’environ 1 E-04 s/m3

• Selon le Guide des règlements du NRC (NRC Regulatory Guide 1.109) : le facteur de conversion de dose pour l’inhalation, y compris l’absorption par la peau (D/I), est de 4.05 E-02 Sv/GBq

• Temps d’exposition (T) : 10 minutes?

Amusez-vous ! Souvenez-vous que cette rubrique s’adresse à vous !

Envoyez-moi vos réponses et vos sugges-tions pour les prochains numéros au secrétariat de l’ACRP ou par courriel à [email protected].


Student Corner

Campus Emergency First Response Teamsby / par Leah Shuparski

RésuméVoici la deuxième d’une série d’entrevues avec des professionnels de la radioprotec-tion et de la sécurité radiologique dans divers domaines. Le but de ces entrevues est d’aider les étudiants à se faire une idée des différentes options de carrière en radio-protection, ainsi que de permettre aux lecteurs du Bulletin de l’ACRP d’ apprendre davantage au sujet de certains de leurs pairs. Dans le présent numéro, l’Association a interviewé William Bateman, étudiant de 4e année en kinésiologie à l’Univer-sité McMaster et directeur de l’équipe du programme de secouriste opérationel Students’ Union Emergency First Response Team de l’Université McMaster.

LS: What is MSU EFRT’s mandate?

WB : Its mandate is to provide rapid emergency medical services, free of charge, to the entire McMaster community.

LS: How does the team operate?

WB : Well, we are funded by the McMaster Students’ Union for our school-year program, and the University funds our summer operation. But McMaster Parking and Security Services is our big operating partner. They dispatch us to our calls, and they manage the scene.

LS: How many responders do you have? Do they get paid?

WB : All of our responders are volun-teers. Right now, we have 28 full-time members, with another 5 active alumni members.

Do you know what campus fi rst

response teams do? How they

are organized? How you, as a

radiation safety professional,

can partner with them to ben-

efi t everyone?

To fi nd the answers to these

questions, I interviewed William

Bateman, a 4th year Kinesiology

student at McMaster University

and the program director of

the McMaster Students’ Union

Emergency First Response

Team (MSU EFRT).


Student Corner

LS: What about HAZMAT? Do you carry specialized equipment for that sort of thing?WB : We don’t carry any special HAZMAT equipment. We’re more first-aid geared. We do carry N95s, Tyvek gowns, and other basic PPE, but we rely on Health Physics and the McMaster Environmental and Occupational Health and Safety Services to deal with the heavy-duty stuff. If we were ever dispatched to a call where HAZMAT was involved, we would depend on them to ensure the scene is safe and only provide first aid once we got their go-ahead.

LS: Have you worked with Health Physics at all?WB : Last year, Health Physics gave responders a tour of the reactor and some of the hot labs. Health Physics and reactor staff showed our responders where some potential hazards could exist. Most of them weren’t even radiation related! But I think it was a great help for the responders to actually tour the facility. We also have a radiation safety protocol in the works that is in its final planning stages.

LS: Do you have advice for radiation safety professionals looking to forge links with their campus first response team?

WB : Well, I think just talking about the basics like facility access, the team’s standard of care, and the general flow of a call is a good start. If the facility has limited access, who will meet the respond-ers at the door to let them in? Should responders bring special PPE with them, or can they get that in the facility before entering the scene? What equipment does the first response team carry? Are there any features in your facility that respond-ers need to be aware of? Once you both understand, in general, how a call will flow, you can then decide what sorts of training and what level of co-operation are required.

If you would like more information on the MSU EFRT or campus emergency fi rst response teams in Canada, go to www.msu.mcmaster.ca/efrt or www.acert.ca.

LS: Why do you need a first response team when local emergency medical ser-vices (EMS) exist?

WB : Our team is not a replacement for an ambulance. We are a complement to Hamilton’s EMS. Their service has an average response time of 9 minutes, whereas our response time is 2 to 3 minutes. In life-threatening situations, rapid treatment of the patient is essential. For instance, when a patient is in cardiac arrest, the faster a defibrillator is on scene and in use, the better the patient’s odds of surviving.

LS: What types of calls does the team typically receive?

WB : Our calls vary from a student who requires a tensor wrap for a sprained ankle to a patient who is in anaphylactic shock and requires epinephrine. We might respond to individuals who are having a seizure, have been burnt, have fainted (lost consciousness), or are having difficulty breathing.


Student Corner

IntroductionIn recent years, many theoretical and experimental methods for understanding organ motion and tumour localization have been investigated in radiotherapy treatment (Bortfeld, Jiang, & Rietzel, 2004; Bortfeld, Jokivarsi, Goitein, Kung, & Jiang, 2002; Dietrich, Tucking, Nill, & Oelfke, 2005; Grozinger et al., 2006). The effects of organ and tumour motion on target localization are key concerns for Intensity Modulated Radiotherapy (IMRT) optimization. Image Guided Radiotherapy (IGRT) techniques provide the accuracy for beam delivery and concentrate the radiation dose to the tumour, while spar-ing dose to healthy tissue. In radiotherapy, factors such as organ motion, tumour displacement, and the physical immobili-zation set-up are critical for the accuracy of treatment. The problem of organ motion also has been a focus of concern for many years in medical imaging, producing effects such as blurring and artifacts on the image, and this in turn has stimulated research in CT (Computed Tomography), MRI (Magnetic Resonance Imaging), and PET-CT (Positron Emission Tomography-Computed Tomography) imaging (Ford, Mageras, Yorke, & Ling, 2003; Frank et al., 2005; Keall et al., 2004; Lemke et

4-D Organ Motion Effectvia Image Guided Radiotherapy in IMRT Optimization

Mehdi Saberi and Dianne CameronRadiation Therapy Program, Department of Physics, Laurentian University, Sudbury, ON

al., 2004; Steenbakkers et al., 2006; von Siebenthal, Cattin, Gamper, Lomax, & Szekely, 2005).

The first step in studying the effect of organ motion is to understand the anatomical and physiological behaviour of the organ that produces motion; the second step is to create a proper math-ematical model in terms of the anatomy of the organ; and the third step is to apply a relevant model to its global realistic location, which will then be used to optimize the IGRT technique in tracking the motion. The success of the third step mainly depends on the degree to which the motion interferes with the accurate delineation of both the target volume and the reference point in treatment planning. The geometrical variation of the target is usually compensated for by modifying the amount of dose delivered, with an added margin for clinical target volume (CTV) and planning target volume (PTV). The expansion of the margin for CTV is, of course, a trade-off, which results in more dose being delivered to neighboring healthy tissue.

In lung cancer and breast cancer, the main concerns are the patient’s breath-

ing and heartbeat during treatment, as this motion causes target displacement and artifacts in dose delivery (Seppen-woolde et al., 2002). In prostate cancer, the effect of geometrical uncertainties in the prostate from related organ motion is another example of a complication in tumour localization (Sohn et al., 2005). Organ motion is a common problem for IMRT and conformal techniques, where the control of beams and dose delivery in IMRT is handled by computer software; it raises concerns about systematic errors during motion tracking in multi-leaf col-limator (MLC) leaves, along with CTV displacement. However, recent advances in IMRT optimization and IGRT have presented those working with IMRT in the radiotherapy field with new prospects for applications. The IGRT techniques deal directly with tumour motion for resolving the problem of target delineation and beam targeting for margin movement in CTV. Most IGRT developments are focused in two problem areas: (1) real-time 4-D imaging; and (2) the on-board imag-ing system that is based on the imaging device’s registration (due to intra-fraction organ motion).

In recent issues of the Bulletin, we featured papers by David Cooper, the winner of the 2007 Anthony J. MacKay Student Paper Contest, and Maxim (Max) Mitchell, the 2008 win-ner. In this issue, we are pleased to share the 2nd place paper from 2008, written by Mehdi Saberi and his supervisor, Dianne Cameron, both from the Radiation Therapy Program at Laurentian University.

CRPA’s student paper contest is held on a yearly basis. The contest prize includes an all-expenses-paid trip to the annual CRPA conference, which will be held in Montreal, Que-bec, this year. The winning paper is also published in the Bulletin.

CRPA/ACRP

Anthony J. MacKayStudent Paper Contest Runner Up


Student Corner

Overview of the StudyIn our study, we focused primarily on a real-time 4-D imaging system for respi-ratory gating in order to track tumour motion in the lung, with the goal of enhancing IMRT optimization in the treatment of lung cancer. The mathemati-cal model of organ motion was studied to improve the cost functions in the IMRT algorithm, as well as to select the best tools based on individual patients. We used an elastic belt sensor and the active breath-ing control (ABC) technique, which were designed to work experimentally with our in-house-built static and moving phan-toms. The dosimetric measurements were analyzed to evaluate errors in simulations, using both the static and moving phan-toms. IMRT verification was accomplished by comparing the Monte Carlo simulation with film dose dosimetry. To assess dosim-etric errors between the IMRT technique and the conformal field, we used the Chi square method to statistically evaluate the effects of hot and cold spots in both plans after beam irradiation (Bakai, Alber, & Nusslin, 2003). We also found some problems with the 4-D imaging technique related to organ motion and the weakness of the mathematical function in the IMRT model due to motion effects.

Materials and MethodsPhantom ConstructionOur experiment was designed to evalu-ate a static and a motion situation, using a lung phantom-equivalent tissue and an imaginary solid tumour set in lung tissue. The phantom was made of cork, with a polystyrene ball to simulate the tumour and polystyrene layers assembled in a block that was shaped for the three regions of the thorax, lung, and tumour (Figure 1). The outer layer of the thorax region was 18 cm wide and 22 cm long, and the lung was 9 cm wide and 16 cm long. The depth measured from the

anterior surface of the thorax phantom to the midline of the target was 6, 9, and 12 cm, respectively. Several optical markers were set on the surface of the phantom in order to determine the isocenter during immobilization in the CT simulation.

In-house Phantom Set-upThe phantom was set up in two positions for the static and motion states. For the motion state, the phantom was placed on a table and connected to a mechanical motor; the motion induced by the motor mimicked the sinusoidal pattern of the human respiratory system. The signal was transferred to a pressure sensor that was attached to an elastic belt, which in turn was attached to the phantom for simulat-ing the amplitude pattern of the patient’s breathing. The cyclical breathing activity of exhalation and inhalation was con-trolled by the mechanical motor, which drove the phantom to produce a suitable gating system, similar to human respira-tion. The 4-D CT scans acquired from the patients in our clinic at the Tübingen University Hospital (in Germany) were set up for a thorax respiratory state, which

generates a gating pattern based on each patient’s breathing. The data sets gener-ated by the sinusoidal moving phantom were then compared with those of lung-cancer patients in the clinic (Figure 2).

Active Breathing ControlThe active breathing control (ABC) device effectively reduces respiratory motion by bringing about a temporary pause in breathing at a desired breathing state (Cheung, Sixel, Tirona, & Ung, 2003; Dawson et al., 2001). It allows temporary immobilization of respiratory motion by implementing a breath hold at a pre-defined lung volume and airflow direc-tion. When a patient reaches this pre-defined lung-volume level, during either inspiration or expiration, the airflow is temporarily blocked, thereby immobiliz-ing the breathing motion. The radiation source is turned on at this point. The ABC device consists of a laptop display monitor for the operator, a standup wide-screen display for the patient, a position-ing device, a VacuSac for immobilization, an at-hand abort switch and a connection

Figure 1: Lung phantom equivalent (left); Different sizes of cork lung equivalent (centre); Optical markers on phantom (right)

Figure 2: (a) Scanning static phantom; (b) Moving phantom


Student Corner

for nasal devices so that the treatment can be delivered during the predetermined phase of the breathing cycle when the location of the tumour is known.

Before the process is begun, a physicist or dosimetrist explains to the patient how the Active Breathing Coordinator™ works and how to interpret the data that will appear on the Active Breathing Coordina-tor™ monitor that has been set up for the patient. The process begins when, with the device’s mouthpiece in place, abort switch in hand, and connections made to the monitoring equipment, the patient is instructed to practice a relaxed breathing pattern that will help clinicians identify a point in inspiration at which the patient can comfortably hold his or her breath for 12 to 15 seconds. In the second step, the patient is brought to the CT imaging scanner with the Active Breathing Coor-dinator™, the stereotactic positioning device, and the VacuSac (for immobiliza-tion) in place. In the third step, CT slices are acquired when the Active Breathing Coordinator™ is activated in concert with the patient’s breath hold. The operators see the same Active Breathing Coordina-tor™ display screen in the CT control area that the patient sees in the scan room. The CT images are then used to develop a treatment plan that will be executed on a subsequent day. In the last step, the accel-erator beam is turned on when the patient reaches the predetermined breath-hold point and the Active Breathing Coordina-tor™ is engaged. Technicians supervise the process from the Linac (linear accelera-tor) control room via the patient video monitor and the laptop Active Breathing Coordinator™ display monitor. The beam may be switched on and off 10 to 20 times during the course of a single fraction. A preliminary test of the ABC technique in our clinic, with accessory devices and a sample of a predetermined sinusoidal exhale and inhale breathing pattern, is shown in Figure 3.

Respiratory Gating System with 4-D CTThe respiratory gating system is based on the synchronization of the image data with the respiratory motion. The system

is equipped with a 4-D CT scan (Siemens Medical Solutions, Germany), a respira-tory gating system (RGS) from Japan, an elastic belt, a pressure sensor, and accessory immobilization devices (Figure 4). The pressure sensor is fixed in the patient’s abdominal (chest) region with a special elastic belt. (The RGS with 4-D CT imaging was used to study 26 lung-cancer patients at the Tübingen University Hospital Oncology Clinic [Kleshneva, Muzik, & Alber, 2006].) We used the RGS to obtain data on the respiratory motion of a patient’s abdominal region during the delivery of treatment as a way to achieve optimal accurate treatment planning. The RGS makes signal amplitude measure-ments with a repetition rate of 40 Hz. The system’s Syngo software (Siemens Medical Solutions, Germany) uses projections

corresponding to a certain respiratory phase to perform retrospective gating for image reconstruction. This reconstruction is performed with projections integrated over a 250-ms window, starting from a given phase. The tension of the belt puts pressure on the sensor during the patient’s breathing activity, and the signal from the sensor is amplified and translated to the scanner. The process of exhaling and

inhaling is interpreted as alternate low and high signals, where the lower signal ampli-tude corresponds to the low pressure of the exhalation phase and the higher ampli-tude to the high pressure of the inhalation phase. The Syngo software first deter-mines the beginning of the rising slope of the breathing curve as the inhale point and the beginning of the falling slope as the exhale point and then plots a curve that is linearly scaled from the 0% inhale to 100% exhale phase. Of course, the real respiratory curve is different for each patient and depends on several factors: (1) the effects of the heartbeat presenting as low amplitude; (2) the irregularity of the physiological pattern of respiration; (3) the signal-to-noise ratio of accessory devices; and (4) the distortion of results due to the patient’s movement, age, and sex.

Results and DiscussionTo evaluate the results of the respiratory motion of the RGS and the ABC device in our clinical setting (the Oncology Clinic in Tübingen), we compared our static and moving phantoms for verification with the IMRT planning and the conformal field. The dosimetric aspect of dose profiles

Figure 3: ABC set-up in clinic.

Figure 4: Set-up of elastic belt for RGS on patient


Student Corner

in both the static and moving phantoms was measured by analyzing the film dose and the Monte Carlo simulation along the beam’s central axis—the dosimetric measurement showed an average of ±2% accuracy. (For the sake of simplicity, we classified the ABC and RGS methods as IGRT techniques.) We also studied the effect of organ motion by mimicking the lung tissue-equivalent phantom, as this allowed us to evaluate the effect of tumour motion during the optimizing phase of the IMRT technique.

This comparison highlighted the effect of IGRT and IMRT techniques on increas-ing treatment accuracy through deliver-ing more dose to the target volume and sparing dose to the organs at risk (Hunt-zinger et al., 2006). In their study, Chan, Bortfeld, and Tsitsiklis (2006) showed that mathematical modeling of organ motion requires prior knowledge of the anatomical and physiological behaviour of the organ. Indeed, much effort has gone into designing a more robust algorithm, through increasing the efficiency of IGRT while considering tumour motion. The mathematical function that is imple-mented for the IMRT system appears as an objective function, with motion param-eters for each individual plan.

The IGRT methods we used in our experiment were fundamental for track-ing respiratory motion and, in the end, allowed us to effectively optimize the IMRT planning system. We began by com-paring the dosimetric measurements of the static and moving phantoms by mea-suring the dose profiles for film dosimetry in each phantom. Both the static and the moving phantoms were irradiated with 6 MV and 15 MV Elekta Linac machines in 10 dose fractions of 7 Gy; in each case, the result was a more uniform dose distribution in the cork region than in the polystyrene lung-equivalent tissue. Also, because of electron disequilibrium and the inhomogeneous configuration of cork density, the beam penumbra in the target was steeper in the field-edge area. This effect increased in significance when the beam energy was increased from 6 MV to 15 MV, except for the penumbra effects. We were able to adjust the differences in dose profile by averaging the whole

cycle of motion in each beam irradiation, which improved the conformal field and the IMRT plan. In general, the dosimet-ric measurement for film dose profiles was in agreement with the Monte Carlo

calculation (Figure 5). However, when evaluating the radiobiological effects of motion in our future work, we intend to add our dose-profile results as a constraint function to determine if this will improve IMRT optimization. The effect of the air gap and the film set-up inside the phan-toms should also be taken into account for possible dose misalignment and dosi-metric errors when the static and moving phantoms are evaluated from the beam’s central axis.

In addition, we assessed the capability of the ABC device to reproduce lung-tumour position. Our results demon-strated that the reproducibility of tumour position during each treatment session is possible and that the exhale and inhale hold phases depend, for the most part, on the maximum threshold of each phase, which is different for each patient. The patient’s deep-breathing reaction also plays an important role in obtaining the opti-mal exhale pattern. However, some factors may be barriers to using ABC even for the same patient, such as the patient’s physical and mental ability to follow the instruc-tions; the location of the CTV margin in terms of the location of GTV; the devia-tion pattern of the patient’s breathing; and random errors by technicians in the immobilization set-up. Previous investi-gators who have used these techniques found that the exhale reproducibility is different from the inhale pattern during the breath hold, giving somewhat better

results for the exhale breath-hold phase (Dawson et al., 2001; Keall et al., 2004).

Based on our analysis of the RGS device, we found that the exhale and inhale curve data produced from each

phase could be corrected, manually or automatically, point by point in each breathing cycle. This correction allowed us to synchronize exactly a part of the patient’s 100% exhale and 0% inhale respiratory pattern, referred to technically as offline or online points. The offline points sit linearly between the amplitude scaling of one exhale to the next inhale phase, which is edited in terms of clinical data for individual patients. In our clinic, these offline routine points are developed as a computer algorithm that allows us to automatically correct the online points into offline points for each breathing cycle during the process of acquiring images by 4-D CT scan. External factors, such as the heartbeat and the pressure of the diaphragm’s movement, may influence the amplitude peak of offline points, which makes it difficult to draw a general paradigm for tracking organ motion. The signal-to-noise ratio of the sensor on the elastic belt worn by the patient can also affect the exhale and inhale amplitude during scanning and produce a discrep-ancy in the editing of the offline and online points for respiratory motion. Research on optimizing the RGS, particu-larly in the offline determination of the respiratory phases (Kleshneva et al., 2006), is ongoing.

Another area we investigated was the issue of robust IMRT optimization for geometrical variations of organ motion, a subject that has been studied by numer-

Figure 5: Comparison of dose fi lm with Monte Carlo beam profi le (left and centre); Error dose comparison (right)


Student Corner

ous research institutes in recent years (Bortfeld et al., 2002; Chan et al., 2006; Halabi, Craft, & Bortfeld, 2006). The key problems in this area are related to the complexity of motion modeling, based on organ behaviour, which in turn makes accurate beam delivery to the target loca-tion even more complicated. Essentially, the root of this problem should be found in the mathematical nature of motion, but it is not entirely resolved for chaotic and non-linear partial and differential equa-tions. Some recent attempts have been made to solve this problem using a statisti-cal distribution function, which seeks a solution by converging to local minima in a global objective function (Alber & Nus-slin, 1999). Our experiment with static and moving phantoms demonstrated that the best way to handle motion during beam irradiation is to control the CTV movement by adding the margin around the PTV. Bortfeld et al. (2004) confirmed that the intra-fraction movement of CTV in the IMRT planning system happens during the fractions, as well as fraction by fraction for inter-fraction movement. This problem is further complicated by multi-organ motion: for instance, the effect of respiratory motion and heartbeat in lung cancer, and the effect of both bladder and rectum motion during treatment for pros-tate cancer (Seppenwoolde et al., 2002).

The basis of the IMRT planning system is optimization, which is defined by mathematical objectives and constraints. In order to prescribe the maximum dose to the tumour while sparing surrounding normal tissue, the IMRT system is opti-mized by a linear iteration loop algorithm (Birkner, Yan, Alber, Liang, & Nusslin, 2003). The challenge in inverse IMRT planning is to maintain a trade-off situa-tion, which is defined by a cost function, to maintain a high dose for the target and a low dose for normal tissue. The cost function mathematically defines a limit in terms of the physical dose volume, as well as the biological objectives of the plan, which analyzes the dose distribu-tions based on equivalent uniform dose (EUD). An important concept in expand-ing the IMRT plan, EUD was developed for the most part by Niemierko (1997, 1999), which is the dose which, if given

uniformly to an organ or structure, would lead to the same biological/clinical effect as a given non-uniform dose distribution. Mathematically, the EUD is suggested by Niemierko (1999), as:

Where di is the dose in voxel i , N is the number of voxels in the region of interest (ROI), and a is called the volume parameter, which will be a tissue-specific parameter that may be positive or nega-tive. Both the negative and positive values of “a “are useful in constructing objective functions and constraints based on EUD. In the Hyperion IMRT planning system (Alber, Birkner, & Nusslin, 2002), the EUD is used to control the mean dose for serial and parallel organs. In the case of the lung, the EUD is set close to the physi-

cal mean dose in order to compensate for breathing motion during treatment.

The Hyperion IMRT system, which is fully implemented by the Alber group in Tübingen University Hospital, optimizes treatment plans through a pencil beam kernel and a Monte Carlo simulation that increase the accuracy of treatment plan-ning, especially for complex cases such as head and neck cancer and prostate cancer. The aim of our experiment was to imple-ment a robust function for Hyperion—by developing a new objective function with a parametric motion variable—that would allow us to deal with respiratory motion problems. This function requires, first,

prior knowledge of target displacement during beam delivery, knowledge that was provided by the static and moving phan-toms, using 4-D CT scan imaging; then, transference into the Hyperion IMRT system; and, finally, irradiation by the Linac machine to produce dosimetric mea-surements for the phantom dose profile analysis. Using these steps, we compared the static and moving phantoms, using the conformal field plan and the IMRT sys-tem, by evaluating their dose distributions. The dose evaluations—completed by the Chi square method (similar to the gamma function evaluation)—compare the hot and cold spots of the conformal field with the IMRT plan. Our results demonstrated the value of choosing the IMRT system over the conformal field; specifically, there were fewer hot spots, especially around the organs at risk, and better dose sparing around the CTV, without adding more margins to the actual plan (Figure 6).

We also studied the motion of a multi-leaf collimator (MLC) in terms of organ motion by evaluating the fluence map profiles of plans in each segment, which are programmed in the Hyperion IMRT by calculating the voxel segments individually for each beam. Our results showed more monitor unit (MU) during motion, in comparison with the static phantom, which can be compensated for by increased iteration in the planning system. The issue of how to simultane-ously optimize the movement of the MLC with organ motion is still under investigation, however. It may lead to new

Figure 6: Gamma function comparison of IMRT with conformal fi elds


Student Corner

techniques, such as arc IMRT therapy or IMRT stereotactic radiotherapy, which will open up new applications for the MLC in sweeping the field, based on the geometri-cal variations of an organ (Litzenberg, Moran, & Fraass, 2002). Our experiment revealed that the fluence map produced by the MLC in our system had better dose coverage around a tumour (despite moving the phantom during irradiation) and that IMRT techniques provide better coverage

of organs at risk than occurred during the static conformal phase of the treatment process. Specifically, there was a 0.5 Gy root mean square (RMS) excess dose for organ at risk (OAR) which was the trade-off dose compensation that was optimized in the Hyperion IMRT planning system through consultation among radiation oncologists and medical physicists at our clinic. The biological DVH (dose volume histogram) of the two plans (Figure 8)

ConclusionsOrgan motion during radiotherapy is a major concern for delivering an accurate dose to the volume of a tumour, while preventing an excess dose to normal tissue. The results of our experiment demonstrated that the effect of respiratory motion on target volume can decrease the accuracy of dose measurements in the planning system. We estimated that the maximum error for our moving phantom was greater than for our static phantom by about 47%, compared with the conformal field. The dosimetric measurement for our film dose profile was in good agree-ment with the Monte Carlo calculation of our static phantom, although the dose-profile analysis of the moving phantom is still under investigation. The unifor-mity of fluence maps for both the static and moving phantoms was evaluated by individual beam fields using a gradient fluence segment in the Hyperion IMRT system, which was also differentiated by the Chi square gamma evaluation that was developed at our clinic. The dose differ-ence revealed by the gamma evaluation method illustrated the advantage of using the IMRT system over the conformal-field system, because of decreasing hot spots on organs at risk.

We confirmed that the development of IGRT techniques, along with the IMRT planning system, substantially increases accuracy, to the extent that it eliminates the margins for CTV with PTV and directly addresses the problem of target definition and beam targeting. After studying the ABC and the GRS methods of analyzing the effects of organ motion in lung-cancer patients at the Tübingen Cancer Centre, we found that the ABC method did not reduce the margin con-sistently for all patients because of their individual differences in breath hold and complications during treatment. Activat-ing the threshold during the breath hold, in terms of the patient’s tolerance, is a challenging task for the ABC method, which requires further modification. The gating respiratory system (GRS) had a bet-ter correlation for breathing control, based on an offline analysis algorithm of one complete exhale (100%) and inhale (0%)

Figure 7: Fluence map for IMRT (left) and conformal fi elds (right)

Figure 8: The biological DVH of the IMRT plan

of the target volume than that provided by the conformal field (Figure 7).

When we compared the biological effects of the IMRT and the conformal field systems with those of the static and moving phantoms, we found that more dose sparing occurred during the motion

showed good agreement with our analyti-cal dose profiles. Nonetheless, there is still a need to understand a tumour’s biologi-cal response in terms of its motion, a need that has recently attracted research by many functional imaging groups (PET-CT) (Frank et al., 2005).


Student Corner

Alber, M., Birkner, M., & Nusslin, F. (2002). Tools for the analysis of dose optimization: II. Sensitivity analysis. Physics in Medicine and Biology, 47(19), N265–270.

Alber, M., & Nusslin, F. (1999). On the appropriateness of the probability model for series type complications. Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology, 52(1), 85–86.

Bakai, A., Alber, M., & Nusslin, F. (2003). A revision of the gamma-evaluation concept for the comparison of dose distributions. Physics in Medicine and Biology, 48(21), 3543–3553.

Birkner, M., Yan, D., Alber, M., Liang, J., & Nusslin, F. (2003). Adapting inverse planning to patient and organ geometrical variation: Algorithm and implementation. Medical Physics, 30(10), 2822–2831.

Bortfeld, T., Jiang, S. B., & Rietzel, E. (2004). Effects of motion on the total dose dis-tribution. Seminars in Radiation Oncology, 14(1), 41–51.

Bortfeld, T., Jokivarsi, K., Goitein, M., Kung, J., & Jiang, S. B. (2002). Effects of intra-fraction motion on IMRT dose delivery: Statistical analysis and simulation. Physics in Medicine and Biology, 47(13), 2203–2220.

Chan, T. C., Bortfeld, T., & Tsitsiklis, J. N. (2006). A robust approach to IMRT optimization. Physics in Medicine and Biology, 51(10), 2567–2583.

Cheung, P. C., Sixel, K. E., Tirona, R., & Ung, Y. C. (2003). Reproducibility of lung tumor position and reduction of lung mass within the planning target volume using active breathing control (ABC). International Journal of Radiation Oncology, Biology, Physics, 57(5), 1437–1442.

Dawson, L. A., Brock, K. K., Kazanjian, S., Fitch, D., McGinn, C. J., Lawrence, T. S., et al. (2001). The reproducibility of organ position using active breathing control (ABC) during liver radiotherapy. International Journal of Radiation Oncology, Biology, Physics, 51(5), 1410–1421.

Dietrich, L., Tucking, T., Nill, S., & Oelfke, U. (2005). Compensation for respiratory motion by gated radiotherapy: An experi-mental study. Physics in Medicine and Biology, 50(10), 2405–2414.

Ford, E. C., Mageras, G. S., Yorke, E., & Ling, C. C. (2003). Respiration-correlated spiral CT: A method of measuring respiratory-induced anatomic motion for radiation treatment planning. Medical Physics, 30(1), 88–97.

Frank, S. J., Chao, K. S., Schwartz, D. L., Weber, R. S., Apisarnthanarax, S., & Macapinlac, H. A. (2005). Technology insight: PET and PET/CT in head and neck tumor staging and radiation therapy planning. Nature Clinical Practice Oncology, 2(10), 526–533.

Grozinger, S. O., Rietzel, E., Li, Q., Bert, C., Haberer, T., & Kraft, G. (2006). Simulations to design an online motion compensation system for scanned particle beams. Physics in Medicine and Biology, 51(14), 3517–3531.

Halabi, T., Craft, D., & Bortfeld, T. (2006). Dose-volume objectives in multi-criteria optimization. Physics in Medicine and Biology, 51(15), 3809–3818.

Huntzinger, C., Munro, P., Johnson, S., Miettinen, M., Zankowski, C., Ahlstrom, G., et al. (2006). Dynamic targeting image-guided radiotherapy. Medical Dosimetry: Official Journal of the American Association of Medical Dosimetrists, 31(2), 113–125.

Keall, P. J., Starkschall, G., Shukla, H., Forster, K. M., Ortiz, V., Stevens, C. W., et al. (2004). Acquiring 4D thoracic CT scans using a multislice helical method. Physics in Medicine and Biology, 49(10), 2053–2067.

Kleshneva, T., Muzik, J., & Alber, M. (2006). An algorithm for automatic determination of the respiratory phases in four-dimen-sional computed tomography. Physics in Medicine and Biology, 51(16), N269–276.

Lemke, A. J., Niehues, S. M., Amthauer, H., Rohlfing, T., Hosten, N., & Felix, R. (2004). Clinical use of digital retrospective

image fusion of CT, MRI, FDG-PET and SPECT — Fields of indications and results [Klinischer Einsatz der digitalen retrospektiven Bildfusion von CT, MRT, FDG-PET und SPECT -- Anwendungsgebiete und Ergebnisse]. Rofo, 176(12), 1811–1818.

Litzenberg, D. W., Moran, J. M., & Fraass, B. A. (2002). Incorporation of realistic delivery limitations into dynamic MLC treatment delivery. Medical Physics, 29(5), 810–820.

Niemierko A. A generalized concept of equivalent uniform dose (EUD). Med. Phys. 26(6):1101, 1999.

Niemierko, A. “Reporting and analyzing dose distributions: A concept of equivalent uniform dose,” Medical Physics. 24, 103–110 (1997)

Seppenwoolde, Y., Shirato, H., Kitamura, K., Shimizu, S., van Herk, M., Lebesque, J. V., et al. (2002). Precise and real-time measurement of 3D tumor motion in lung due to breathing and heartbeat, measured during radiotherapy. International Journal of Radiation Oncology, Biology, Physics, 53(4), 822–834.

Sohn, M., Birkner, M., Yan, D., & Alber, M. (2005). Modelling individual geometric variation based on dominant eigenmodes of organ deformation: Implementation and evaluation. Physics in Medicine and Biology, 50(24), 5893–5908.

Steenbakkers, R. J., Duppen, J. C., Fitton, I., Deurloo, K. E., Zijp, L. J., Comans, E. F., et al. (2006). Reduction of observer variation using matched CT-PET for lung cancer delineation: A three-dimensional analysis. International Journal of Radiation Oncology, Biology, Physics, 64(2), 435–448.

von Siebenthal, M., Cattin, P., Gamper, U., Lomax, A., & Szekely, G. (2005). 4D MR imaging using internal respiratory gating. Med.ImageComput.Comput.Assist.Interv.Int.Conf.Med.Image Comput.Comput.Assist.Interv., 8(Pt 2), 336–343.

References

AcknowledgementsThis work was supported by Laurentian University, Sudbury, Canada, and The University Hospital for Radiation Oncology, Tübingen, Germany. We would like to extend our special thanks to Jodi Ploquin, MSc, CLSO, the Chair of the Student Contest Committee, for her ideas and support of this paper.

phase. We were able to confirm this result in 26 lung-cancer patients at Tübingen University Hospital, which allowed us to optimize an accurate and fast algorithm for reconstructing 4-D CT images.

Finally, using our phantom mod-els with the Hyperion IMRT planning system (which was developed by the Alber research group in Tübingen University Hospital for dosimetric verification), we illustrated that a better understanding of

a mathematical model of organ motion could improve the optimization process in IMRT planning and that eliminating the breathing pattern builds up a more realistic model of respiratory motion. The effects of organ motion in IMRT continue to be an area of active research that requires more effort and expansion, especially the development of mathemati-cal optimization in clinical IMRT tech-niques.


Résumé :Une nouvelle façon de communiquer entre dosimétristes internes est en voie d’exploration à l’aide de tech-nologies existantes sur Internet. Un groupe a d’ailleurs été formé sur le site Web bien connu de Facebook. Le groupe encouragera l’échange d’infor-mation et fournira des ressources aux individus qui en ont besoin.

by Gary H. Kramer

The homepage of the network will change dramatically as members join and discussions begin. You can contact members of the network directly simply by clicking on their name and following the on-screen instructions for sending a message.

Success of the NetworkThe FaceBook group is reasonably flexible, and the success of the network is in the hands of its users. As currently configured, the group site can be used for general postings, specific discussion topics, and downloading photos and videos. Links that direct users to other sites of interest can be added to the network’s site.

The idea for an International Internal Dosimetry Network came out of dis-cussions held at the World Health Organization’s Radiation Emergency Medical Preparedness and Assistance Network (REMPAN) meeting held in Buenos Aires, Argentina, on October 15–17, 2008. It was recognized that the surge capacity of many countries may be insufficient to deal with an incident, acci-dental or intentional, that contaminates a large number of people and that an electronic network of regional experts in internal dosimetry could help to alleviate this problem. Those present at the meet-ing felt that a network could be used to quickly assess health risks so that further action could be taken, if required.

In addition to being a source of internal dosimetry experts who can be called upon to assist when an incident overwhelms the response capabilities of local/regional/national institutions, the International Internal Dosimetry Network could also• advance scientific co-operation and

inter-institutional relationships,

• foster and promote the exchange of ideas and techniques,

• further collaboration on research and development in the internal dosimetry field,

• generally broaden the scientific experi-ence of all parties involved, and

• provide a forum for discussing issues related to internal dosimetry.

Typically, setting up such a network requires a host organization to step forward to dedicate resources and server space. However, because this would likely involve a lengthy approval process, a differ-ent approach was chosen to demonstrate the effectiveness (or lack of effectiveness) of such a network. Of the several options available in cyberspace, FaceBook was chosen for a first trial. How to create a FaceBook account and how to join the network are described next.

Joining FaceBookThere is no fee for joining FaceBook, and the proce-dure for joining is simple.

Using an Internet browser, type www.facebook.com into the address bar and press enter. The FaceBook login/sign-up page will appear.

Type your name and a valid email address in the Sign Up area. (Note: fictitious first and/or last names are often used on FaceBook but using fictitious names defeats the pur-pose of this network: to connect internal dosimetry experts and resources from around the world.) FaceBook will send notifications to your email address when network events are posted.

Click on the green Sign Up button; a validation page will appear. After you complete and submit the validation, an email is sent to the address you entered on the sign-up page. The sign-up process is not complete until you activate the link in the email sent to you by FaceBook.

Once you have activated the link, FaceBook opens at the “Getting Started” section, which consists of three pages. How-ever, most of this section can be skipped.

Joining the International Internal Dosimetry NetworkTo find the International Internal Dosimetry Network, click on the “Groups” icon on the right side of the FaceBook page. Type “International Internal Dosimetry Network” in the search box and press enter. Then click on “Join Group,” which is found on the right side of the page. Click on “Join” to complete your enrolment. The network’s homepage will eventually appear.

International Internal Dosimetry Network


Book Review / Critique de livre

Although I haven’t used a gamma spectrometer for several years, at one time in my career I used the instrument frequently. I started working on Ge(Li) systems and later graduated to HPGe systems. However, having had no formal training in gamma spectrometry, my knowledge of the basic theory was limited

to what I could learn from Glenn Knoll’s Radiation Detection and Measurement and a number of Application Notes supplied by the manufacturer. Practical Gamma-ray Spectrometry is the book I could have used 20 years ago.

Gordon Gilmore, formerly with the Activation Analysis Group at the Universi-ties Research Reactor in Risley, is now the director of Nuclear Training Services Ltd., which offers training courses on gamma spectrometry in the United Kingdom. He co-authored the first edition of this book, which was published in 1995, with John Hemmingway. This edition has been extensively rewritten due, in part, to copy-right issues with Hemmingway’s estate.

The book is a complete introduction to the subject. Chapters on radioactive decay and gamma-ray interactions lead into chapters on semi-conductor detectors and supporting electronics, including power supplies, preamplifiers, ADCs, and multi-channel analyzers. Chapters devoted to statistics (detection limits, etc.), resolution, calibration, and software follow. Although not stimulating reading, the two chapters on system set-up and trouble shooting will be extremely useful to practising gamma spectroscopists. Much more interesting are the final chapters on high-count-rate and low-count-rate systems and on gamma spectrometry of naturally occurring radio-active materials. Dr. Gilmore emphasizes quality assurance and proper laboratory technique throughout the book. He also

review by Michael Grey

Gordon Gilmore (Chichester, United Kingdom: John Wiley & Sons, 2008)

Practical Gamma-ray Spectrometry (2nd ed.)

Résumé

Il y a 20 ans, j’ai déjà utilisé un spec-tromètre gamma et ce livre, Practical Gamma Spectromerty, m’aurait été bien utile. Il s’agit de la 2e édition large-ment ré-écrite de la première édition co-rédigée par John Hemmingway et publiée en 1995. Bien qu’elle four-nisse une introduction complète à la spectrométrie gamma, cette nouvelle édition exige une connaissance de base de l’électronique et un peu d’ex-périence en matière de spectrométrie gamma. Une bonne connaissance de la statistique est aussi essentielle puisque l’auteur parle de comptage de statistique et des limites de détection, en plus de donner menus détails sur les incertitudes. Le livre comprend des références à des ressources sur Internet et l’auteur a créé un site qui vérifie les spectra et fournit des tableurs, des données nucléaires et des liens vers la plupart des fabricants et organismes mentionnés.

discusses the strengths and weaknesses of a number of spectrometry systems that are currently available and of nuclear data sets available from system suppliers and other sources. There are sections on scintilla-tion detectors and X-ray systems, but these subjects are not discussed in depth.

The author assumes readers have a basic knowledge of electronics; some previ-ous experience in gamma spectrometry would be an advantage. A good knowl-edge of statistics is also essential since the author discusses, in detail, counting statistics, detection limits, and uncertain-ties. Several sections (particularly the chapters on system set-up and trouble shooting) could be skipped by the casual reader, but, as noted earlier, they contain useful reference material for practising spectroscopists.

The book includes references to resources that are available on the Inter-net. The author has created a website that not only provides spreadsheets, test spectra, nuclear data, and links to most of the manufacturers and organizations he mentions in the book but also includes a list of corrections and a discussion page.

Practical Gamma-ray Spectrometry is the text used in the training courses offered by Dr. Gilmore’s company. The full course is not available in North America, but the author is currently setting up an online version of the one-day introduc-tory course, which will be available free of charge.


Coming Events / Réunions à venir• CRPA conference May 23–29, 2009, Montréal, Québec

• American Conference of Governmental Industrial Hygienists (ACGIH) annual conference

May 30–June 4, 2009, Toronto, Ontario

• Canadian Nuclear Society / Société Nucléaire Canadienne annual conference

May 31–June 3, 2009, Calgary, Alberta

• Health Physics Society, 54th Annual Conference July 12–16, 2009, Minneapolis, Minnesota

Canadian Radiation Protection Association (CRPA), jointly with Campus Radiation Safety Offi cer (CRSO), invites you to Montréal, the biggest French speaking city in North America, for a conference in radiation protection with a human taste! The conference will review all aspects of Radiation Safety. A parallel program focusing on Campus Radiation Safety will be organized.

New this year, participants will have an opportunity to participate in a preparatory training course for the CRPA registration exam (CRPA (R) on the Friday of the conference.

For more information, visit our website:http://www.crpa-acrp.com/en

l’Association canadienne de radioprotection (ACRP) conjointement avec le Campus Radiation Safety Offi cer (CRSO), vous invite à Montréal, la plus grande métropole francophone d’Amérique, pour une conférence en radioprotection à saveur humaine ! Les caractéristiques ergonomiques du travail et les facteurs conditionnant les performances feront l’objet d’une considération spécifi que.

Une primeur cette année, nous offrirons un cours de préparation à l’examen de l’ACRP R(ACRP), qui aura lieu le vendredi du congrès.

Pour les détails, visitez notre site Web:http://www.crpa-acrp.com/fr

Index to Advertisers

Alara Consultants Inc. pg. 3

Canberra Co. pg. 22–23, 44

F & J Specialty Products,Inc. pg. 38

Gamble Technologies, Inc. pg. 2

Lou Champagne Systems pg. 8

Mirion Technologies pg. 29

Radiation Measurement Systems, Inc. pg. 17

Stuart Hunt & Associates pg. 6

Technical Management Services, Inc. pg. 15

For more information about advertising in the CRPA Bulletin ACRP, please contact Michelle Communications:

Michelle Boulton ph: 306-343-8519 email: [email protected]


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ph: 613-253-3779email: [email protected]

Deadlines

Materials must be received by the editor no later than the following dates:

Spring ......................January 15Summer ...................April 15Fall ...........................July 15Winter .......................October 15

Advertising

While advertisements are sought after and accepted to offset the production costs of the Bulletin, the newsletter is published primarily for, and on behalf of CRPA / ACRP members. There-fore inclusion of advertisements is entirely at the discretion of the association. CRPA / ACRP reserves the right to reject, omit, or cancel any advertisements that are not in keeping with the professional nature of the Bulletin or in any other way inappropriate for our members.

Advertorials

Advertorials are a new advertising feature for the Bulletin and are available at the same rate as display advertising. If a client requires assis-tance with writing, editing, or production of their advertorial, these services can be negotiated with the production company responsible for producing the Bulletin. For more information, contact Michelle Boulton at [email protected].

Publishing Offi ce

For rates, technical specifi cations, deadlines and any information about advertising, contact the publishing offi ce.

Michelle Communications

ph: (306) 343-8519email: [email protected]

ALARA Consultants Inc.Allan Seitz9556-27 Ave.Edmonton, AlbertaCanada T6N 1B2tel: 780-944-2557fax: 780-944-2558www.alaraconsultants.com

Atomix Nuclear Services Inc.Bruce ConningUnit 1, 250 Thompson DriveCambridge, OntarioCanada N1T 2E3tel: 519-624-7233fax: 519-624-6853www. atomixnuclear.com

Bubble Technology Industries Inc.Dr. Robert Noulty31278 Highway 17Chalk River, OntarioCanada KOJ 1J0tel: 613-589-2456fax: 613-589-2763www.bubbletech.ca

Canadian Association of Medical Radiation TechnologistsAnn RobertsonSuite 1000, 85 Albert StreetOttawa, OntarioCanada K1P 6A4tel: 613-234-0012fax: 613-234-1097www.camrt.ca

Canadian Nuclear Safety Services Inc.Fergus DevereauxBox 2592, 83 Water Street NorthSt. Marys, OntarioCanada N4X 1A4tel: 519-284-0699fax: 519-284-1389www.nuclearsafety.ca

Canberra Co.Jim OutosWest - 50B Caldari RoadConcord, OntarioCanada L4K 4N8tel: 905-660-5373fax: 905-660-9693www.canberra.com

DURRIDGE Company, Inc.Derek Lane-Smith7 Railroad Avenue, Suite DBedford, MassachusettsUSA 01730tel: 781-687-9556fax: 781-687-0955www.durridge.com

Energy Solutions CanadaRon LeblondHead Offi ce190 Wilkinson Rd., Unit #2Brampton, OntarioCanada L6T 4W3tel: 800-665-7736fax: 905-450-8523www.monserco.com

CRPA Corporate Members /ACRP Membres corporatifs

F & J Specialty Products Inc.F. M. Gavila404 Cypress Rd.Ocala, Florida USA 34472tel: 352-680-1177fax: 352-680-1454www.fjspecialty.com

Gamble TechnologiesJanice Langaigne6535 Millcreek Drive, Unit 58Mississauga, OntarioCanada L5N 2M2tel: 905-812-9200 or 800-268-2735fax: 905-812-9203www.gtl.ca

Miron TechnologiesLouis Biacchi2652 McGaw AvenueIrvine, California USA 92614tel: 888-419-10000 or 949-419-1000, ext 2316fax: 949-296-1130www.mirion.com

Harpell Associates Inc.1272 Speers Road, Unit 2Oakville, OntarioCanada, L6L 2X4tel: 905-825-2588 800-387-7168fax: 905-825-0234www.harpellassociates.com

Hopewell Designs, Inc.Joy Garrett5940 Gateway DriveAlpharetta, Georgia USA 30004tel: 770-667-5770fax: 770-667-7539www.hopewelldesigns.com

J L Shepherd & AssociatesMary Shepherd1010 Arroyo AvenueSan Fernando, CaliforniaUSA 91340-1822tel: 818-898-2361fax: 818-361-8095www.jlshepherd.com

Landauer, Inc2 Science RoadGlenwood, Illinois USA 60425tel: 708-755-7000fax: 708-755-7011www.landauerinc.com

Lou Champagne Systems Inc.Lou ChampagneUnit 6B - 1195 North Service Rd. WestOakville, OntarioCanada L6M 2W2tel: 905-338-1176fax: 905-338-6426www.louchampagnesystemsinc.com

Marshield – Division of Mars Metal Co.David Holden4140 Morris DriveBurlington, OntarioCanada L7L 5L6tel: 800-381-5335fax: 905-637-8841www.marshield.comwww.marsmetal.com

National Dosimetry Services Radiation Protection BureauAnn Rouette775 Brookfi eld Road, 6301DOttawa, OntarioCanada K1A 1C1tel: 800-261-6689fax: 613-957-8698 800-252-6272www.hc-sc.gc.ca/hecs-sesc/nds

Radiation Measurement SystemsErnie Franzese81 Romeo CrescentWoodbridge, OntarioCanada L4L 7A2tel: 905-856-5950fax: 905-851-7473email: [email protected]/com

Radiation Safety Institute of CanadaTina de Geus1120 Finch Ave. West, Suite 607Toronto, Ontario, Canada M3J 3H7tel: 416-651-9090, ext. 25fax: 416-650-9920www.radiationsafety.ca

Ray-Bar Engineering LtdVince WohlerPO Box 415697 Foothill BoulevardAzusa, California USA 91702tel: 626-969-1818fax: 626-969-6510www.raybar.com

Stuart Hunt and AssociatesTrevor Beniston20 Rayborn CrescentSt. Albert, AlbertaCanada T8N 5C1tel: 780-458-0291 or 800-661-4591fax: 780-459-0746www.stuarthunt.com

Technical Management Services, Inc.Robin RivardPO Box 226New Hartford, ConnecticutUSA 06057tel: 860-738-2440fax: 860-738-9322www.tmscourses.com

Uni-Vert Tech Inc.Willy Rhein3737 Notre-Dame OuestMontreal, QuebecCanada H4C 1P8tel: 514-573-2858fax: 514-937-9440www3.sympatico.ca/rad.tech/english.html


Canadian Radiation Protection AssociationAssociation canadienne de radioprotection

2009 Advertising Rates &Specifi cations

About CRPA/ACRP

Canadian Radiation Protection Association / Association canadienne de radioprotection (CRPA / ACRP) was incorpo-rated in 1982. The objectives of the association are

• to develop scientific knowledge and practical means for protecting all life and the environment from the harmful effects of radiation consistent with the optimum use of radiation for the benefit of all,

• to further the exchange of scientific and technical infor-mation relating to the science and practice of radiation protection,

• to encourage research and scientific publications dedicated to the science and practice of radiation protection,

• to promote educational opportunities in those disciplines that support the science and practice of radiation protection,

• to assist in the development of professional standards in the discipline of radiation protection; and

• to support relevant activities of other societies, associations, or organizations, both national and international.

Members of the association are drawn from all areas of radia-tion protection, including hospitals, universities, the nuclear power industry, and all levels of government.

The CRPA/ACRP Bulletin

The association publishes the Bulletin four times per year and distributes it to all members. Corporate members are listed in each issue of the Bulletin.

Advertising in the Bulletin

Advertising in the CRPA Bulletin ACRP delivers your message to the heart of the radiation protection community through an association and a publication readers know and trust. The editorial content of the Bulletin delivers the insights, contacts, information, advice, and valuable solutions that people in radiation protection need to stay at the forefront of their profession.

If you want to reach the radiation protection community, the targeted nature of the Bulletin will get your message out to people who are interested in what you sell or do.

Circulation

Published by CRPA/ACRP, the Bulletin is distributed free to the association’s 400 members. In addition, the newsletter is available by subscription to non-members, such as libraries.


Publishing Schedule

The Bulletin is published quarterly. Exact publication dates may vary; however, our target deadlines are as follows:

Issue DistributionAdvertising Deadline

winter March October 15

spring June January 15

summer September April 15

fall December July 15

Mechanical Specifi cations

• page size 8.375” x 10.875”

• average of 32 pages per issue

• four colour process throughout

Display Advertisement Sizes / Rates

SizeDimensions

(width x height)

Rates

membernon-

member

full-page 7.375” x 9.375” $450 $650

full-pagewith bleeds

8.625” x 11.375” $450 $650

half-page3.625” x 9.375”

7.375” x 4.625”$275 $400

quarter-page3.625” x 4.625”

7.375” x 2.375”$200 $300

Other Considerations

• Advertorials will be accepted at the same rates as display advertising. These must arrive print ready (see Requirements below). If writing, editing, proofreading, or design services are required, these may be negotiated independently with the production team (email Michelle Boulton at [email protected]).

• Preferential placement may be available for an additional $50.

• All rates are for full colour (at no additional cost).

• When more than one advertisement is booked and paid at one time, the following frequency discounts apply:

- 2 ads . . . save 5% - 3 ads . . . save 10% - 4 ads . . . save 15%

Requirements

All advertisements must be supplied as print-ready digital files. If design services are required, this should be negotiated with the production team independently (email Michelle Boulton at [email protected]).

Digital files must comply with the following specifications:

• All ads must be CMYK (four colour process)

• Accepted file formats include tiff, eps, jpg, or pdf

• Ads should be at least 300 dpi at the finished size

• Ads must conform to the pre-defined sizes

For questions regarding advertisement specifications, digital requirements, or submission guidelines, please contact Michelle Boulton at [email protected].

SubmissionsTo place an ad in the Bulletin, contact

Michelle Boulton 2501 Blain AvenueSaskatoon, SK S7J 2B7

ph 306-343-8519fax 306-477-5418

email [email protected]

Documents

Canadian Radiation Protection Association Association ...crpa-acrp.org/home/wp-content/uploads/2019/10/CRPA-Bulletin-30-1-web.pdfcal means for protecting all life and the environment