i

A Practical Guide

WHO/SDE/OEH/02.2

G L O B A L

S O L A R

U V I N D E X

A joint recommendation of:

World Health Organization

World Meteorological Organization

United Nations Environment Programme

International Commission on Non-Ionizing Radiation Protection

WHO Library Cataloguing-in-Publication Data

Global Solar UV Index: A Practical Guide.

A joint recommendation of the World Health Organization,World Meteorological Organization, United Nations Environment Programme,and the International Commission on Non-Ionizing Radiation Protection

1. Ultraviolet rays – adverse effects 2. Sunlight – adverse effects 3. Radiationmonitoring – instrumentation 4. Radiation monitoring – standards 5. Reference values 6. Health education 7. Environmental exposure – preventionand control 8. Manuals

ISBN 92 4 159007 6 (NLM classification: QT 162.U4)

© World Health Organization 2002

All rights reserved. Publications of the World Health Organization can be obtainedfrom Marketing and Dissemination,World Health Organization, 20 Avenue Appia,1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email:bookorders@who.int). Requests for permission to reproduce or translate WHOpublications – whether for sale or for noncommercial distribution – should beaddressed to Publications, at the above address (fax: +41 22 791 4806; emailpermissions@who.int).

The designations employed and the presentation of the material in this publication donot imply the expression of any opinion whatsoever on the part of the World HealthOrganization concerning the legal status of any country, territory, city or area or of itsauthorities, or concerning the delimitation of its frontiers or boundaries. Dotted lineson maps represent approximate border lines for which there may not yet by fullagreement.

The mention of specific companies or of certain manufacturers’ products does notimply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors andommissions excepted, the names of proprietary products are distinguished by initialcapital letters.

The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damagesincurred as a result of its use.

Graphic icons designed by Pauls SlossPrinted in SwitzerlandAvailable at http://www.who.int/uv/

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Contents

Preface iv

Introduction 1

The Global Solar UV Index – An Educational Tool 4

Reporting the UV Index – The Basic Scheme 6

Sun Protection Messages – Creating Variety 10

Educational Concepts and Their Practical Implementation 12

Annex

A Health Effects of UV Radiation Exposure 15

B Internet Links: Organizations Reporting the UV Index 19

C The UV Index 21

D Graphic Presentation of the UV Index 22

E Additional Sun Protection Messages 23

F List of Contributors 25

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Preface

A marked increase in the incidence of skincancers has been observed in fair-skinnedpopulations worldwide since the early 1970s.This is strongly associated with personalhabits in relation to sun exposure and itsultraviolet (UV) component, and the societalview that a tan is desirable and healthy.Educational programmes are urgentlyneeded to raise awareness of the damagingeffects of UV radiation, and to encouragechanges in lifestyle that will arrest the trendtowards more and more skin cancers.

The Global Solar UV Index (UVI) described inthis document is a simple measure of the UVradiation level at the Earth’s surface and anindicator of the potential for skin damage. It serves as an important vehicle toraise public awareness and to alert peopleabout the need to adopt protectivemeasures when exposed to UV radiation.TheUVI was developed through an internationaleffort by the World Health Organization(WHO) in collaboration with the UnitedNations Environment Programme (UNEP), theWorld Meteorological Organization (WMO),the International Commission on Non-

Ionizing Radiation Protection (ICNIRP) andthe German Federal Office for RadiationProtection (Bundesamt für Strahlenschutz,BfS) (see Annex F for list of contributors).Since its initial publication in 1995, severalinternational meetings of experts (LesDiablerets, 19941; Baltimore, 19962; LesDiablerets, 19973; Munich, 20004) have beenconvened with the aim to harmonize thereporting of the UVI and to improve its use asan educational tool to promote sunprotection.

This practical guide, prepared by EvaRehfuess, is based on the consensus reachedat the Munich meeting, and is intended to beused by national and local authorities and non-governmental organizations active inthe area of skin cancer prevention, as well as meteorological offices and media outletsinvolved with UVI reporting. This publication can serve as an entry point for thedevelopment and implementation of anintegrated public health approach to sunprotection and skin cancer prevention.

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1 Report of the WMO meeting of experts on UVB measurements, data quality and standardization of UV indices, Les Diablerets,Switzerland, 22–25 July 1994. Geneva,World Meteorological Organization, 1995 (Global Atmosphere Watch, No. 95).

2 Educating the public about the hazards of ultraviolet radiation. Summary report. International workshop, Baltimore, 26–28 August 1996. Aberdeen Proving Ground MD, U.S. Army Center for Health Promotion and Preventive Medicine, 2001.

3 Report of the WMO–WHO meeting of experts on standardization of UV indices and their dissemination to the public, Les Diablerets, Switzerland, 21–24 July 1997.Geneva,World Meteorological Organization, 1997 (Global Atmosphere Watch,No. 127).

4 UV index in practical use. Proceedings of an international workshop. Munich, Federal Office for Radiation Protection, Instituteof Radiation Hygiene, in press.

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Everyone is exposed to UV radiation fromthe sun and many artificial sources used inindustry, commerce and recreation.Emissions from the sun include light, heatand UV radiation.

The UV region covers the wavelength range100–400 nm and is divided into threebands:

UVA (315–400 nm)

UVB (280–315 nm)

UVC (100–280 nm)

As sunlight passes through theatmosphere, all UVC and approximately90% of UVB radiation are absorbed byozone, water vapour, oxygen and carbondioxide. UVA radiation is less affected bythe atmosphere.

Therefore, the UV radiation reaching theEarth’s surface is largely composed of UVAwith a small UVB component.

Introduction

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SUN ELEVATION

The higher the sun in the sky, the higherthe UV radiation level. Thus UV radiationlevels vary with time of day and time ofyear. Outside the tropics, the highestlevels occur when the sun is at itsmaximum elevation, at around midday(solar noon) during the summer months.

LATITUDE The closer to equatorial regions, thehigher the UV radiation levels.

CLOUD COVERUV radiation levels are highest undercloudless skies but even with cloud cover,UV radiation levels can be high.Scattering can have the same effect asthe reflectance by different surfaces andthus increase total UV radiation levels.

ALTITUDE At higher altitudes, a thinneratmosphere absorbs less UV radiation.With every 1000 metres increase inaltitude, UV radiation levels increase by10% to 12%.

OZONEOzone absorbs some of the UV radiationthat would otherwise reach the Earth’ssurface. Ozone levels vary over the yearand even across the day.

GROUND REFLECTION

UV radiation is reflected or scattered tovarying extents by different surfaces, e.g.fresh snow can reflect as much as 80% ofUV radiation, dry beach sand about 15%and sea foam about 25%.

UV RADIATION LEVELS ARE INFLUENCED BY:

Small amounts of UV radiation are beneficialfor people and essential in the production ofvitamin D. UV radiation is also used to treatseveral diseases, including rickets, psoriasisand eczema. This takes place under medicalsupervision and the benefits of treatmentversus the risks of UV radiation exposure area matter of clinical judgement.

Prolonged human exposure to solar UVradiation may result in acute and chronichealth effects on the skin, eye and immunesystem. Sunburn and tanning are the bestknown acute effects of excessive UVradiation exposure; in the long term, UVradiation-induced degenerative changes incells, fibrous tissue and blood vessels lead topremature skin ageing. UV radiation can alsocause inflammatory reactions of the eye,such as photokeratitis.

Chronic effects include two major publichealth problems: skin cancers and cataracts.Between two and three million non-melanoma skin cancers and approximately132000 melanoma skin cancers occurglobally each year.While non-melanoma skincancers can be surgically removed and arerarely lethal, malignant melanoma substan-tially contributes to mortality rates infair-skinned populations. Some 12 to 15million people are blind from cataracts.According to WHO estimates, up to 20% ofthese cases of blindness may be caused orenhanced by sun exposure, especially inIndia, Pakistan and other countries of the“cataract belt” close to the equator.

Furthermore, a growing body of evidencesuggests that environmental levels of UVradiation may enhance the risk of infectiousdiseases and limit the efficacy of vaccina-tions. Please see Annex A for a detaileddescription of the health effects of exposureto UV radiation.

People’s behaviour in the sun is consideredto be a major cause for the rise in skin cancerrates in recent decades. An increase inpopular outdoor activities and changedsunbathing habits often result in excessiveexposure to UV radiation. Many peopleconsider intensive sunbathing to be normal;unfortunately, even children, adolescentsand their parents perceive a suntan as asymbol of attractiveness and good health.

Sun protection programmes are urgentlyneeded to raise awareness of the healthhazards of UV radiation, and to achievechanges in lifestyle that will arrest the trendtowards more and more skin cancers. Beyondthe health benefits, effective educationprogrammes can strengthen nationaleconomies by reducing the financial burdento health care systems caused by skin cancerand cataract treatments. Billions are spentworldwide to treat these diseases, many ofwhich could have been prevented ordelayed.The Global Solar UV Index should bean important element of an integrated andlong-term public health approach to sunprotection.

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WHAT IS THE GLOBAL SOLAR UVINDEX?The Global Solar UV Index (UVI) describes thelevel of solar UV radiation at the Earth’ssurface. The values of the index range fromzero upward – the higher the index value, thegreater the potential for damage to the skinand eye, and the less time it takes for harm tooccur.

WHY DO WE NEED THE UVI?A marked increase in the incidence of skincancer in fair-skinned populations worldwideis strongly associated with excessive UVradiation exposure from the sun; it may alsobe associated with the use of artificial UVradiation sources such as sunbeds. Currentevidence indicates that personal habits inrelation to sun exposure constitute the mostimportant individual risk factor for UVradiation damage. The UVI is an importantvehicle to raise public awareness of the risksof excessive exposure to UV radiation, and toalert people about the need to adoptprotective measures. Encouraging people toreduce their sun exposure can decreaseharmful health effects and significantlyreduce health care costs.

HOW SHOULD THE UVI BE USED?This educational tool should be used as anintegral component of a programme to informthe public about UV radiation health risks andsun protection, and to change people’sattitudes and behaviour with respect to UV

radiation exposure. The UVI should especiallyaim at vulnerable and highly-exposed groupswithin the population,e.g.children and tourists,and should inform people about the range ofUV radiation-induced health effects includingsunburn, skin cancer and skin ageing, andeffects on the eye and immune system.Educational messages should emphasize thatthe risk of adverse health effects from UVradiation exposure is cumulative, and thatexposure in everyday life may be as importantas exposure during vacations in sunny climates.

HOW IS THE UVI PRESENTED?UV radiation levels and therefore the valuesof the index vary throughout the day. Inreporting the UVI, most emphasis is placedon the maximum UV radiation level on agiven day. This occurs during the four-hourperiod around solar noon. Depending ongeographical location and whether daylightsaving time is applied, solar noon takes placebetween local noon and 2 p.m. The mediausually present a forecast of the maximumUV radiation level for the following day.

WHERE IS THE UVI REPORTED?In many countries the UVI is reported alongwith the weather forecast in newspapers, onTV and on the radio; however, this is usuallydone only during the summer months.Annex B lists a series of Internet links thatprovide the UVI for a range of countries andin many different languages.

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The Global Solar UV Index AN EDUCATIONAL TOOL

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WHAT IS THE IMPORTANCE OF AHARMONIZED UVI?Many countries use the UVI to promote sunprotection. Surveys suggest that a largepercentage of the public is aware of theexistence of the UVI but does not understandits meaning or usefulness. These problemsare related to the lack of standardizedmessages associated with the UVI. The UVI is

clearly defined as an educational tool, and itsuse must be based on effective communica-tion with the public and the media.Uniformity of UVI presentation, anduniformity of sun protection messagesassociated with different UVI values, willfacilitate the delivery of a simple and relevantmessage, and will help to familiarize peoplewith this important concept.

Burn times have been used in manycountries as this simple concept can bedirectly translated into action. However,people tend to interpret burn times to meanthat there is a safe level of unprotected sunexposure. Hence, relating UVI values to “timeto burn” or “safe tanning time” sends out thewrong message to the public. The UVI

should not imply that extending exposuresis acceptable. Although the priority goal ofprimary skin cancer prevention is to avoidsunburn, cumulative UV radiation exposureplays a major role in developing skin cancerand promotes damage to the eyes andimmune system.

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REPORTING UVI VALUESThe UVI is a measure of the intensity of UVradiation on the Earth’s surface that is relevant to effects on the human skin.

• UVI reports should present at least thedaily maximum value. When forecasting orreporting daily maxima, a 30-minute timeaverage value should be used. Wherecontinuous observations are available, a5–10 minute average is useful to displayshort-term changes.

• The UVI should be presented as a singlevalue rounded to the nearest whole number.

• However, when cloud cover is variable, theUVI should be presented as a range ofvalues. UVI forecasts should include effectsof cloud on UV radiation transmissionthrough the atmosphere. Programmes notincorporating cloud effects in theirforecasts should refer to them as a “clearsky” or “cloud free” UVI.

UVI values are grouped into exposurecategories (Table 1). The national meteorologyoffice or media service may choose to reportthe exposure category, the UVI value or rangeof values, or both.

LOW < 2

MODERATE 3 TO 5

HIGH 6 TO 7

VERY HIGH 8 TO 10

EXTREME 11+

Reporting the UV IndexTHE BASIC SCHEME

Table 1: UV radiation exposure categories

REPORTING BURN TIMES IS NOT RECOMMENDED.

EXPOSURE CATEGORY UVI RANGE

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1 Fitzpatrick TB, et al, reported in TB Fitzpatrick and JL Bolognia, Human melanin pigmentation: Role in pathogenesis of cutaneousmelanoma. In: Zeise L, Chedekel MR, Fitzpatrick TB (eds.) Melanin: Its role in human photoprotection. Overland Park, KS,ValdenmarPublishing Company, 1995:177-82.

SKIN TYPE CLASSIFICATION BURNS IN THE SUN TANS AFTER HAVING BEEN IN THE SUN

Table 2: Classification of skin types (adapted from TB Fitzpatrick and JL Bolognia, 19951)

Always SeldomUsually Sometimes

Sometimes UsuallySeldom Always

Naturally brown skinNaturally black skin

A SIMPLE AND RELEVANT MESSAGEAcceptance by the general public of the UVIas useful daily information is the ultimategoal. In order to achieve this, the messagesmust be simple and easily understood.Reporting the UVI with relevance to therecipient will allow people to put recommendations into practice and accept

the UVI as a guide to healthy, sun-protectivebehaviour.

From a public health point of view,it is especially important to protect the most vulnerable population groups. Based onthe finding that more than 90% of non-melanoma skin cancers occur in skin types Iand II (Table 2), the basic protective messagesassociated with the UVI should focus on fair-skinned people who tend to burn. Children,who are particularly sensitive to UV radiation,require special protection.

Even though the incidence of skin cancer islower in dark-skinned people, they are never-theless susceptible to the damaging effectsof UV radiation, especially to the effects onthe eye and immune system. Additionalmessages at the national or local level willallow the particular needs of otherpopulation sub-groups to be addressed.

These should take into account differences inclimate and culture, the perception of UVradiation risks in the population, and thestage of sun protection education.

l.ll.

lll.lV.

V.VI.

Melano-compromised

Melano-competent

Melano-protected

Figure 1: Enjoy the sun but enjoy it safely

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THE BASIC SUN PROTECTION MESSAGES

Figure 2: Recommended sun protection scheme with simple “sound bite” messages

NO PROTECTIONREQUIRED

PROTECTIONREQUIRED

EXTRAPROTECTION

You can safely stay

outside!

Seek shade during midday hours!

Slip on a shirt, slop on sunscreen andslap on a hat!

Avoid being outside duringmidday hours!

Make sure you seek shade!

Shirt, sunscreen and hat are a must!

• Limit exposure during midday hours.• Seek shade.• Wear protective clothing.• Wear a broad-brimmed hat to protect

the eyes, face and neck.• Protect the eyes with wrap-around-

design sunglasses or sunglasses withside panels.

• Use and reapply broad-spectrumsunscreen of sun protection factor(SPF)15+ liberally

• Avoid tanning beds.• Protect babies and young children: this

is particularly important.

Shade, clothing and hats provide the bestprotection – apply sunscreen to parts of thebody that remain exposed, like the face andhands. Sunscreen should never be used toprolong the duration of sun exposure.

Two different concepts of sun protectionhave been proposed: a binary response with a defined threshold UVI value beyondwhich sun protection is recommended, or agraded response with increasing UVI valuesthat would involve the successive use ofdifferent sun-protective measures. There is little scientific basis to support the latter: ifsun protection is required, this shouldinclude all protective means, i.e. clothing,sunglasses, shade and sunscreen (Figure 1).Nevertheless, a graded approach is relevantin the sense that more sun protection isneeded at higher UV radiation levels.

Even for very sensitive fair-skinned people,the risk of short-term and long-term UVradiation damage below a UVI of 3 is limited,and under normal circumstances noprotective measures are needed. Above thethreshold value of 3, protection is necessary,and this message should be reinforced at UVIvalues of 8 and above.

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GRAPHIC PRESENTATION OF THE UVIA standard graphic presentation of the UVIpromotes consistency in UVI reporting onnews and weather bulletins, and serves toimprove people’s understanding of the UVIconcept. Ready-made materials for UVIreporting facilitate successful media uptake,and more than one option is given to allow

different media to cope with technicallimitations.The graphics package (see AnnexD) can be downloaded from the website of WHO’s Global UV Project Intersunhttp://www.who.int/uv/ and includes the UVIlogo, icons for UVI reporting, sunprotection icons, and colour codesfor different values of the UVI.

Figure 3: Examples of UVI graphics

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FALSE TRUE

ADDITIONAL SUNSMART MESSAGESThe basic scheme for UVI reporting and sunprotection can be varied and expandedthrough the use of additional messages atthe national or local level. Messages onsuntanning, sun protection and people’sinability to perceive UV radiation underliethe basic message and can be used in allsettings.

Environment-based, activity-based or riskgroup-based messages can be gearedspecifically to local weather conditions, orthe particular environmental or societalsituation of a given country. Annex E listsexamples of such additional sun protectionmessages adapted from Australia, Canadaand France.

Targeted groups must include children andyoung people (Figure 4), since frequent UVradiation exposure and a history of sunburnduring childhood and adolescence is animportant risk factor for skin cancer, especiallyfor potentially lethal malignant melanoma.Additional messages can also be used to correctcommon misconceptions about UV radiationand its effects on human health (Table 3).

Figure 4: Children require special protection

Sun Protection MessagesCREATING VARIETY

A tan results from your body defending itself against further damagefrom UV radiation.

A dark tan on white skin offers only limited protection equivalent toan SPF of about 4.

Up to 80% of solar UV radiation can penetrate light cloud cover. Hazein the atmosphere can even increase UV radiation exposure.

Water offers only minimal protection from UV radiation, andreflections from water can enhance your UV radiation exposure.

UV radiation is generally lower during the winter months, but snowreflection can double your overall exposure, especially at highaltitude. Pay particular attention in early spring when temperaturesare low but the sun’s rays are unexpectedly strong.

Sunscreens should not be used to increase sun exposure time but toincrease protection during unavoidable exposure. The protection theyafford depends critically on their correct application.

A suntan is healthy.

A tan protects you from the sun.

You can’t get sunburnt on acloudy day.

You can’t get sunburnt while inthe water.

UV radiation during the winteris not dangerous.

If you take regular breaks duringsunbathing you won’t get sunburnt.

If you don’t feel the hot rays ofthe sun you won’t get sunburnt.

Sunburn is caused by UV radiation which cannot be felt. The heatingeffect is caused by the sun’s infrared radiation and not by UV radiation.

UV radiation exposure is cumulative during the day.

Sunscreens protect me so I cansunbathe much longer.

Table 3: UV radiation danger: Facts and fiction

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Specific colours should be used for presentingthe solar UVI. These do not have a scientificbasis but are a means of making the presentation of the UVI more appealing.

The colour coding facilitates variationbetween geographic areas of high and low UVradiation levels, and a basic colour is definedfor each category (Table 4; see also Annex D).

The colour within categories can be gradedto allow for variation at the national levelwhere values often remain within onecategory throughout the summer months(see Annex D).

Not all media will be able to integrate thevariation in colour into their presentation.Television media generally use standardizedmaps and changing the colours may not befeasible due to technical limitations. Similarly,black and white print media will not be ableto use the recommended colour scheme.

EMPHASIZING DANGEROUS HOURSIn countries where UV radiation levels arehigh and where knowledge about UVradiation and sun protection in thepopulation is widespread, a further conceptmay be applied to increase variability. Thiswas introduced in Australia in 2000.

The approach focuses on the hours of the dayduring which the UVI is above a giventhreshold value (Figure 5).While on one day theUVI may reach a value of above 3 for no morethan 30 minutes, on another day it mayremain above 3 for several hours. The adviceto the public emphasizes the need to adoptsun-protective practices during these hours.

Low Moderate High Very high Extreme(1,2) (3,4,5) (6,7) (8,9,10) (11+)

Green Yellow Orange Red PurplePMS 375 PMS 102 PMS 151 PMS 032 PMS 265

USING COLOUR TO INCREASE VARIABILITY

Table 4: Presenting the UVI: International colour codes1

1 The eps graphic files, which are downloadable from the website of WHO’s Global UV Project Intersun http://www.who.int/uv/, willreproduce satisfactorily in most cases, allowing the worldwide reproduction of a standardized colour scheme. Pantone MatchingSystem (PMS) colour references may be used for minor colour correction.

2 The colour scheme currently used by the Bureau of Meteorology, Australia does not comply with the international colour codespromoted in this publication.

Figure 5: A graphic representing dangerous hours(Bureau of Meteorology, Australia)2

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Increased sun exposure has been identifiedas the main reason for the increase in skincancer rates since the early 1970s, and onlychanges in lifestyle can stop this ongoingtrend. Public education aims to improvepeople’s knowledge about the health risks ofexcessive sun exposure, and to achieve achange in attitudes and behaviour. Reducingthe occurrence of sunburn and cumulativeUV radiation exposure over a lifetime willeventually cause skin cancer rates to decline.

It is important that information be presentedin a positive manner that enables people toenjoy the sun safely but at the same timemakes them aware of the need to avoid overexposure. The UVI should form anintegral element of programmes to educatethe public about the health hazards ofexcessive UV radiation exposure.The sectionsbelow address key elements of effectiveeducation campaigns.

MAIN TARGET AUDIENCES AND SUNPROTECTION SETTINGSA majority of a person’s lifetime exposureoccurs before age 18, and sun avoidanceduring childhood has a greater impact onhealth risk reduction than sun protectionduring adulthood. Therefore, children andadolescents should be the primary target foreducation about the sun and how to avoiddamage to health. An effective campaign canhave an enormous impact on public health: achange in people’s behaviour towardseffective sun protection could eliminatemore than 70% of skin cancers in Australia.

Schools are essential for getting the messageacross to young people. Teachers and theirassociations should be encouraged to takeup the cause and include UV radiationawareness and protection projects in theeducational system. Furthermore, all outdoorrecreational sites – beaches, sports centresand swimming pools, zoos and parks –provide a good setting for information aboutUV radiation levels and sun protection.

As a large percentage of many people’slifetime exposure to UV radiation is receivedduring vacations, tourists represent animportant audience for UVI reporting andsun protection advice.

BUILDING NETWORKS ANDALLIANCESIn order to change people's sun exposurehabits and the current societal view thatassociates a tan with good health, long-termstrategies are required. The cooperation ofdifferent sectors is necessary to implementfar-reaching educational strategies andcreate a supportive environment for theintegration of sun protection into the cultureof a country. For this reason, campaigns inmany countries are organized as a collabora-tive effort between different medical andscientific associations, government andspecialized private institutions, andcharitable societies.

Further partners in disseminating themessage may include the tourism industrysuch as airlines, hotel chains and cruise liners,

Educational Concepts and Their Practical Implementation

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national weather bureaux and companiesproducing sun protection items such assunscreen and sunglasses.

EDUCATION• Encourage the use of the UVI as part of

public awareness programmes.• Supply health care professionals,

teachers and carers of children witheducational material for distribution to the public.

• Organize workshops for medical doctorsand other health professionals.

• Establish education programmes forteachers.

• Establish education programmes foroutdoor workers.

• Encourage and support the provision ofshaded areas in schools, playgrounds andparks, and in public places such as busstops and swimming pools.

• Recommend against the use of sunlampsand sunbeds for cosmetic purposes.

• Inform the community of drugs andcosmetics that sensitize the skin to theeffects of UV radiation.

• Enlist weather broadcasters, healthreporters and the media to provide theUVI service to the public.

EVALUATION• Establish national statistics on UV

radiation-induced skin and eye diseases.• Encourage research on UV radiation

related health effects and protectivemeasures.

• Support national programmes andinternational collaboration efforts on UV radiation monitoring and healtheducation.

• Conduct research that monitorsbehavioural, knowledge and attitudinaltrends related to sun protection.

STANDARDS• Facilitate the development of standards

related to sun protection products such assunscreens, clothing, sunbeds andsunglasses to ensure clear and safeguidelines for manufacturers andconsumers.

• Encourage the provision of informationon the degree of UV radiation protectionprovided by sunscreens, eyewear, clothingand other protective measures.

THE ROLE OF NATIONAL GOVERNMENTS

The media should be encouraged to reportthe UVI with their daily weather information,so that people begin to accept this as animportant piece of information in addition tothe news and weather report. The TV, radioand print media provide an essential mediumfor informing the public about the hazards ofUV radiation and the need to adoptprotective measures. They can support local

and national programmes by highlightinghealth concerns, and can even promoteresearch by making the results of new healtheffects or protective devices known to thepublic. To ensure continuing interest in theawareness campaign, it will be necessary toprogressively develop short, clear messagesthat are tailored to the particular medium.

ENSURING MEDIA SUPPORT

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THE ROLE OF LOCAL AUTHORITIES AND HEALTH AGENCIES

USEFUL STRATEGIES INCLUDE:• Holding a press conference at the

launch of a campaign, e.g. in late-spring,where appropriate health professionalsare available for interviews.

• Organizing short seminars for journaliststo educate them about the problems ofexcessive UV radiation exposure and to disseminate the key sun protectionmessages.

• Using the announcements for pressconferences to highlight key issues,followed by press releases that provideclear and simple messages.

• Using human interest stories to get themessage across.

The promotion of the UVI needs to beconducted in a positive and attractive way.The key words are “save”,“protect”and “help”.

THE UVI CAN:✓ save lives ✓ protect good health✓ help preserve youthful complexion

EVALUATING THE EFFECTIVENESSOF A UVI CAMPAIGNA sun awareness programme that uses theUVI as an educational tool aims to improvepeople’s knowledge, and change attitudesand behaviour with respect to sun exposureand sun protection. A well-designedevaluation survey should assess:

• whether members of the general publicunderstand the meaning of the UVI andthe message it carries;

• whether the campaign has changedpeople’s knowledge, attitudes andbehaviour with respect to sun exposure.

• Encourage behaviour change throughsign prompts and educational activities in community and recreation facilities andservices.These could include programmesin schools and kindergartens, the distri-bution of brochures in public buildings,banks, shopping centres and health carecentres, and sun protection fairs wherehealth professionals participate in presen-tations and skin cancer screening.

• Promote creative activities on sunprotection, e.g. fashion shows using UVradiation-protective designs and fabrics,science projects, and competitions.

• Modify the physical environment andpromote the consideration of shade inurban planning and in the modificationof public places.

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Health Effects of UV RadiationExposureANNEX A

Human exposure to solar radiation mayresult in acute and chronic health effects onthe skin, eye and immune system. It is apopular misconception that only fair-skinned people need to be concerned aboutoverexposure to the sun. Darker skin hasmore protective melanin pigment, and theincidence of skin cancer is lower in dark-skinned people. Nevertheless, skin cancersdo occur with this group and unfortunatelythey are often detected at a later, moredangerous stage. The risk of UV radiation-related health effects on the eye andimmune system is independent of skin type.A comprehensive summary and review of UVradiation-related health effects can be foundin the WHO Environmental Health CriteriaMonograph Ultraviolet Radiation1 and in theProceedings of an International Workshop onUltraviolet Radiation2.

SKIN

SUNBURN, SUNTAN AND SKINAGEINGThe best known acute effect of excessive UVradiation exposure is erythema, the familiarskin reddening termed sunburn. In addition,most people will tan from the UV radiationstimulation of melanin production, whichoccurs within a few days of exposure. Afurther, less obvious adaptive effect is thethickening of the outermost layers of

the skin that attenuates UV radiationpenetration to the deeper layers of the skin.Both changes are a sign of damage to theskin. Depending on their skin type,individuals vary greatly in their skin’s initialthreshold for erythema and their ability toadapt to UV exposure. Chronic exposure toUV radiation also causes a number of degen-erative changes in the cells, fibrous tissueand blood vessels of the skin. These includefreckles, nevi and lentigines, which arepigmented areas on the skin, and diffusebrown pigmentation. UV radiationaccelerates skin ageing, and the gradual lossof the skin’s elasticity results in wrinkles anddry, coarse skin.

NON-MELANOMA SKIN CANCERSNon-melanoma skin cancers (NMSC)comprise basal cell carcinoma andsquamous cell carcinoma. These are rarelylethal but surgical treatment is painful andoften disfiguring. The temporal trends of NMSC incidence are difficult to determine,because reliable registration of these cancershas not been achieved. However, specificstudies carried out in Australia, Canada andthe United States, indicate that between the 1960s and the 1980s the prevalence ofNMSC increased by a factor of more thantwo. The risk of NMSC has been examinedwith respect to personal exposure, and the

1 Ultraviolet radiation. An authoritative scientific review of environmental and health effects of UV, with reference to global ozonelayer depletion. Geneva,World Health Organization, 1994 (Environmental Health Criteria Monograph, No. 160).

2 Proceedings of an international workshop on ultraviolet radiation exposure, measurement and protection, St Catherine’sCollege, Oxford, 1999. Radiation Protection Dosimetry, 2000, 91:1-3.

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NMSC is most frequent on parts of the bodythat are commonly exposed to the sun suchas ears, face, neck and forearms. This impliesthat long-term, repeated UV radiationexposure is a major causal factor.

Within some countries there is a clear rela-tionship between increasing incidence ofNMSC with decreasing latitude, i.e. higher UVradiation levels.

MALIGNANT MELANOMAMalignant melanoma (MM), although far lessprevalent than NMSC, is the major cause ofdeath from skin cancer and is more likely tobe reported and accurately diagnosed thanNMSC. Since the early 1970s, MM incidencehas increased significantly, e.g. by an average4% every year in the United States. A largenumber of studies indicate that the risk ofmalignant melanoma correlates with geneticand personal characteristics, and a person’sUV radiation exposure behaviour. Thefollowing is a summary of the main humanrisk factors:

• A large number of atypical nevi (moles) isthe strongest risk factor for MM in fair-skinned populations.

• MM is more common among people with apale complexion, blue eyes, and red or fairhair. Experimental studies have demon-strated a lower threshold erythema andmore prolonged skin reddening inmelanoma patients than in controls.

• High, intermittent exposure to solar UVradiation appears to be a significant riskfactor for the development of MM.

• The incidence of MM in white populationsgenerally increases with decreasinglatitude, with the highest recordedincidence occurring in Australia, where theannual rates are 10 and over 20 times therates in Europe for women and menrespectively.

• Several epidemiological studies support apositive association with history of sunburn,particularly sunburn at an early age.

• The role of cumulative sun exposure in thedevelopment of MM is equivocal. However,MM risk is higher in people with a historyof NMSC and of solar keratoses, both ofwhich are indicators of cumulative UVradiation exposure.

Figure 6: Basal cellcarcinoma

Figure 8: Maligant melanoma

Figure 7: Squamouscell carcinoma

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EYEThe eye is recessed within its orbit andshielded by the brow ridge, the eyebrowsand the eyelashes. Bright light activates theconstriction of the pupil and the squintingreflex to minimize the penetration of thesun’s rays into the eye. However, the effec-tiveness of these natural defences inprotecting against the dangers of UVradiation is limited under extreme conditionssuch as sunbed use or strong groundreflection from sand, water and snow.

Acute effects of UV radiation exposureinclude photokeratitis and photoconjunctivi-tis. These inflammatory reactions arecomparable to a sunburn of the verysensitive skin-like tissues of the eyeball andeyelids, and usually appear within a fewhours of exposure. Both can be very painful,but are reversible and do not result in anylong-term damage to the eye or vision.Extreme forms of photokeratitis are “arc-eye”and “snow blindness”.

Cataracts are the leading cause of blindnessin the world. Proteins in the eye’s lensunravel, tangle and accumulate pigmentsthat cloud the lens and eventually lead toblindness. Even though cataracts appear todifferent degrees in most individuals as theyage, sun exposure, in particular exposure toUVB, appears to be a major risk factor forcataract development.

IMMUNE SYSTEMThe immune system is the body’s defencemechanism against infections and cancers,and is normally very effective at recognizingand responding to an invading micro-organism or the onset of a tumour. Although

the data remain preliminary, there isincreasing evidence for a systematicimmunosuppressive effect of both acute andlow-dose UV radiation exposure.

Animal experiments have demonstrated thatUV radiation can modify the course andseverity of skin tumours. Also, people treatedwith immunosuppressive drugs have agreater incidence of squamous cellcarcinoma than the normal population.Consequently, beyond its role in the initiationof skin cancer, sun exposure may reduce thebody’s defences that normally limit theprogressive development of skin tumours.

Several studies have demonstrated thatexposure to environmental levels of UVradiation alters the activity and distributionof some of the cells responsible for triggeringimmune responses in humans. Consequently,sun exposure may enhance the risk ofinfection with viral, bacterial, parasitic orfungal infections, which has been demon-strated in a variety of animal models.Furthermore, especially in countries of thedeveloping world, high UV radiation levelsmay reduce the effectiveness of vaccines.Since many vaccine-preventable diseases areextremely infectious, any factor that results ineven a small decrease in vaccine efficacy canhave a major impact on public health.

OZONE DEPLETION AND UV-RELATED HEALTH EFFECTSDepletion of the ozone layer is likely toaggravate existing health effects caused byexposure to UV radiation, as stratosphericozone is a particularly effective UV radiationabsorber. As the ozone layer gets thinner, theprotective filter provided by the atmosphere

18

is progressively reduced. Consequently,human beings and the environment areexposed to higher UV radiation levels, andespecially higher UVB levels that have thegreatest impact on human health, animals,marine organisms and plant life.

Computational models predict that a 10%decrease in stratospheric ozone could causean additional 300 000 non-melanoma and4500 melanoma skin cancers and between1.6 and 1.75 million more cases of cataractsworldwide every year.

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Internet Links: OrganizationsReporting the UV IndexANNEX B

WORLDWorld Ozone and Ultraviolet Radiation Data Centrehttp://www.msc-smc.ec.gc.ca/woudc/

WORLDInstitute of Medical Physics and Biostatistics,University of Veterinary Medicine Viennahttp://i115srv.vu-wien.ac.at/uv/uv_online_alt.htm#uvimaps

EUROPEScientific UV Data Management (SUVDAMA)http://www.ozone.fmi.fi/SUVDAMA/

MEDITERRANEAN BASIN (French/English/Spanish/Italian)Environmental Forecast and Information Servicehttp://www.enviport.com/index_en.html

ARGENTINA (Spanish) Regional Centre of Satellite Datahttp://www.conae.gov.ar/iuv/iuv.html

National Meteorological Servicehttp://www.meteofa.mil.ar/

AUSTRALIABureau of Meteorologyhttp://www.bom.gov.au/info/about_uvb.shtml

AUSTRIAInstitute for Medical Physics, University of Innsbruckhttp://www.uibk.ac.at/projects/uv-

index/aktuell/mon_kart_eng.html

CANADA (English/French)Meteorological Service of Canadahttp://www.msc-smc.ec.gc.ca/uvindex/

CZECH REPUBLIC(Czech/English) Czech Hydrometeorological Institutehttp://www.chmi.cz/meteo/ozon/o3uvb.html

FINLAND (Finnish)Finnish Meteorological Institutehttp://www.ozone.fmi.fi/

FRANCE (French) Securité Solairehttp://www.securite-solaire.org

GERMANY(German)Federal Office for Radiation Protectionhttp://www.bfs.de/uvi/index.htm

German Weather Serviceshttp://www.uv-index.de/

GREECE(Greek) Laboratory of Atmospheric Physicshttp://lap.physics.auth.gr/uvindex/

HONG KONG SPECIAL ADMINISTRATIVE REGIONOF CHINAHong Kong Observatoryhttp://www.info.gov.hk/hko/wxinfo/uvindex/english/

uvindex_e.htm

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ISRAEL (Hebrew/English) Israel Weather Forecasthttp://www2.iol.co.il/weather/Edefault.asp

ITALY (Italian/English) Labratory for Meteorology and EnvironmentalModellinghttp://www.lamma.rete.toscana.it/previ/ita/stazlam.htm

JAPAN(English) Shiseido UV Ray Informationhttp://www.shiseido.co.jp/e/e9708uvi/html/index.htm

LUXEMBOURG(French) Meteorological Station of the Lycée Classique de Diekirchhttp://meteo.lcd.lu/

MEXICO(Spanish/English) Mexico City Air Quality Reporthttp://sima.com.mx/sima/df/_zseeng.html

NEW ZEALANDLauder National Institute of Water and Atmospheric Research (NIWA)http://katipo.niwa.cri.nz/lauder/homepg07.htm

NORWAY(Norwegian/English) Norwegian Radiation Protection Authorityhttp://uvnett.nrpa.no/

POLAND(Polish)Institute of Meteorology and Water Managementhttp://www.imgw.pl/

PORTUGAL(Portuguese/English)Meteorological Institutehttp://www.meteo.pt/uv/uvindex.htm

SLOVENIA(Slovenian)Environmental Agency of Sloveniahttp://www.rzs-hm.si/zanimivosti/UV.html

SPAIN(Spanish)National Meteorological Institutehttp://www.inm.es/wwz/fijo/estaciones.html

SWEDEN(Swedish/English) Swedish Radiation Protection Institutehttp://www.smhi.se/weather/uvindex/sv/uvprog.htm

SWITZERLAND(German/French)Federal Office of Public Healthhttp://www.uv-index.ch

TURKEY (Turkish)Scientific and Technical Research Council of Turkeyhttp://www.tubitak.gov.tr/

UNITED KINGDOMThe Meteorological Officehttp://www.met-office.gov.uk/sec3/gsuvi.html

UNITED STATES OF AMERICAThe Weather Channelhttp://www.weather.com/activities/health/skin

National Oceanic and Atmospheric Administration(NOAA) and Environmental Protection Agency (EPA)Climate Prediction Centerhttp://www.cpc.ncep.noaa.gov/products/stratosphere/

uv_index/index.html

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The Global Solar UVI is formulated using the International Commission on Illumination (CIE)reference action spectrum for UV-induced erythema on the human skin (ISO 17166:1999/CIES 007/E-1998). It is a measure of the UV radiation that is relevant to and defined for a horizontalsurface. The UVI is a unitless quantity defined by the formula:

where Eλ is the solar spectral irradianceexpressed in W/(m2.nm) at wavelengthλ anddλ is the wavelength interval used in thesummation. ser(λ) is the erythema referenceaction spectrum, and ker is a constant equalto 40 m2/W.

The determination of the UVI can be throughmeasurements or model calculations. Twomeasurement approaches can be taken: thefirst is to use a spectroradiometer and tocalculate the UVI using the above formula.

The second is to use a broadband detectorthat has been calibrated and programmed togive the UVI directly. Prediction of the solarUVI is achieved with a radiative transfermodel that requires the input of total ozoneand the aerosol optical properties. Aregression model is used to predict the totalozone using the input from ground-basedozone spectroradiometers or from satellites.A good cloud parameterisation is alsorequired unless only clear sky values arereported.

The UV IndexANNEX C

I = k E s d( ). .er

400 nm

λλ λerUV ∫250 nm

Graphic Presentation of the UV IndexANNEX D

Oslo HelsinkiStockholm

Riga

Minsk

KievWarsawBerlin

Prague

ViennaBucharest

Rome

Paris

LondonDublin

Madrid

Rabat

CanaryIslands

Algier Tunis

Tripoli

Cairo

Athens

Ankara Tblisi

Moscow

Tehran

Geneva

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SUNTANNING MESSAGES• Tanning does not stop much UV radiation!

Even when your skin is tanned, limit yourexposure during midday hours, andcontinue to protect yourself.

• Don’t UV OD. Sunburn is literally anindication that your skin has overdosed onUV radiation so Slip! Slop! Slap! and SaveYour Skin.

SUN PROTECTION MESSAGES• Wear sunglasses, a wide-brimmed hat and

protective clothing, and frequently applysunscreen of SPF 15+ to protect yourself.

• Applying sunscreen is not a means toprolong your stay in the sun but to reducethe health risk of your exposure.

• Taking certain medications as well as usingperfumes and deodorants can sensitizeyour skin, causing serious burns in the sun.Ask your pharmacist for advice.

• Sun exposure increases skin cancer risk,accelerates skin ageing and causesdamage to the eyes. Protect yourself!

• Shade is one of the best defences againstthe sun’s radiation. Try to find some shadeduring midday hours when the sun’s UVrays are at their peak.

PERCEPTION OF UV RADIATION• Cloudy weather doesn’t mean you can’t

get burnt. It’s the UV radiation in the sun'srays that burns you and causes skin cancer,and UV radiation can penetrate throughcloud.

• Remember the sun does not need to feelhot to damage your skin and eyes. Thedamage is done by UV radiation, which isnot seen or felt – so don’t be fooled by mildtemperatures.

ACTIVITY-BASED MESSAGES• If you’re out to watch or participate in

(name of event), don’t forget yoursunscreen, hat and long-sleeved shirt. Thatshould be all you need to make sure all yougo home with are great memories oftoday’s events – and not a nasty dose ofsunburn.

• This is a great time to head to the skislopes. High altitudes and fresh snow candouble your UV radiation exposure, sowear sunglasses and sunscreen!

• Going on a sunny vacation? Make sure topack your wide-brimmed hat, sunglassesand sunscreen.

• School break means fun in the sun for thelucky ones. If you’re one of them,remember to pack a hat, sunscreen andsunglasses.

Additional Sun Protection MessagesANNEX E

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• Springtime, gardening time. While tendingyour flower beds, don’t forget to protectyour skin.

ENVIRONMENT-BASED MESSAGES• Identify risky situations. If your shadow is

short or if you are exposed for a long time– protect yourself!

• Watch out! A lot of UV radiation can passthrough clouds.

• In the mountains, UV radiation levelsincrease by approximately 10% with every1000 metres in altitude. Snow reflectioncan double the quantity of UV radiationyou are exposed to.

• Fresh snow can double your UV radiationexposure, so wear sunglasses andsunscreen!

MESSAGES FOR CHILDREN AS ASPECIAL RISK GROUP• Extended sun exposure during childhood

increases the risk of skin cancer later in lifeand can cause serious damage to the eye.

• All children below age 15 have sensitiveskin and eyes – protect them and set agood example for them!

• Children below one year of age must neverstay in direct sun.

• The sun is getting stronger and childrenare exposed to its damaging rays duringlunch and recess. Encourage your childrento use sun protection and to take a breakin the shade.

• Most of our lifetime UV radiation exposureoccurs before age 18. Protect your children… their skin will be healthier and lookyounger throughout their lives.

• Parents – protect your children from thesun. Teach them about avoiding sunexposure and the proper steps for sunprotection.

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L.R. Acosta, SIMA Ministry of theEnvironment (Mexico)

C.B. Archer, South African Weather Bureau(South Africa)

B. Armstrong, New South Wales CancerCouncil (Australia)

A. Bais, Laboratory of Atmospheric Physics,Aristotle University of Thessaloniki (Greece)

J.H. Bernhardt, International Commission forNon-Ionizing Radiation Protection(Germany)

M. Blumthaler, Institut für MedizinischePhysik, Universität Innsbruck (Austria)

C. Boldeman, Karolinska Hospital (Sweden)

W. Bonta, National Conference of RadiationControl (United States)

J. Borkowski, Institute of Geophysics, PolishAcademy of Sciences (Poland)

D. Broadhurst, Meteorological Service ofCanada, Environment Canada (Canada)

E. Breitbart, Dermatologisches ZentrumBuxtehude (Germany)

D. Bressoud, Swiss Federal Office of PublicHealth (Switzerland)

J. Brix, Bundesamt für Strahlenschutz(Germany)

V.L. Buchanan, U.S. Army Center for HealthPromotion and Preventive Medicine (United States)

W.R. Burrows, Meteorological Service ofCanada, Environment Canada (Canada)

F. Carvalho, Institute for Meteorology(Portugal)

J.-P. Césarini, Institut National de la Santé etde la Recherche Médical (France)

P. Césarini, Sécurité Solaire (France)

J. Damski, Finnish Meteorological Institute(Finland)

M. Davis, U.S. Army Center for HealthPromotion and Preventive Medicine (United States)

K. Dehne, Deutscher Wetterdienst(Germany)

Y. Deslauriers, Health Canada (Canada)

C.J. Diaz Leal (Mexico)

H. Dixon, The Cancer Council Victoria(Australia)

List of ContributorsANNEX F

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C. Driscoll, National Radiological ProtectionBoard (United Kingdom)

A. Fergusson, Meteorological Service ofCanada, Environment Canada (Canada)

D. Frei, Swiss Federal Office of Public Health(Switzerland)

R.P. Gallagher, British Columbia CancerAgency (Canada)

R. Greinert, Dermatologisches ZentrumBuxtehude (Germany)

D. Harder, Strahlenschutzkommission(Germany)

R. Harrington, Journalist (Germany)

A. Heimo, Institut Suisse de Météorologie(Switzerland)

D.J. Hufford, U.S. Environmental ProtectionAgency (United States)

S. Human, Technikon Natal (South Africa)

L. Jalkanen, World MeteorologicalOrganization (Switzerland)

M. Janouch, Czech HydrometeorologicalInstitute (Czech Republic)

K. Jokela, Säteilyturvakeskus (Finland)

W. Josefsson, Swedish Meteorological andHydrological Institute (Sweden)

M. Kabuto, National Institute forEnvironmental Studies (Japan)

D. Kastelec, Hyrdometeorological Institute ofSlovenia (Slovenia)

Y.S. Kim, Hanyang University (South Korea)

P. Koepke, Meteorologisches Institut,Universität München (Germany)

A. Kricker, New South Wales Cancer Council(Australia)

A. Kulmala, World MeteorologicalOrganization (Switzerland)

J. Langford, U.S. Army Center for HealthPromotion and Preventive Medicine (United States)

B. Lapeta, Institute of Meteorology andWater Management (Poland)

M. Lehnert, Universität Bochum (Germany)

Z. Litynska, Institute of Meteorology andWater Management (Poland)

C.S. Long, National Weather Service, NationalOceanic and Atmospheric Administration(United States)

A. Manes, Israel Meteorological Service(Israel)

G.F. Mariutti, Istituto Superiore de Sanitá(Italy)

R. Matthes, Bundesamt für Strahlenschutz(Germany)

C. Mätzler, Institute of Applied Physics,University of Bern (Switzerland)

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A. McCulloch, ICI Chemicals and PolymersLtd. (United Kingdom)

R.L. McKenzie, NIWA Lauder (New Zealand)

A.F. McKinlay, National RadiologicalProtection Board (United Kingdom)

R. Meerkoetter, Deutsche Luft- undRaumfahrt, Fernerkundungsdatenzentrum(Germany)

R. Meisner, Deutsche Luft- und Raumfahrt,Fernerkundungsdatenzentrum (Germany)

B. Menne, European Centre for Environmentand Health, World Health Organization(Italy)

M. Miller, World Meteorological Organization(Switzerland)

N. Miloshev, Geophysical Institute (Bulgaria)

M. Miyauchi, Japan Meteorological Agency(Japan)

A. Mylvaganam, International Agency forResearch on Cancer (France)

P. Nemeth, Hungarian MeteorologicalService (Hungary)

M. Norval, Department of MedicalMicrobiology, University of Edinburgh(United Kingdom)

J. Oliviéri, Météo-France (France)

S.P. Perov, Federal Service onHydrometeorology and EnvironmentalControl (Russian Federation)

R. Philipona, World Radiation Centre(Switzerland)

H. Plets, Royal Meteorological Institute(Belgium)

T. Prager, Hungarian Meteorological Service(Hungary)

E.A. Rehfuess, World Health Organization(Switzerland)

M.H. Repacholi, World Health Organization(Switzerland)

L. Rikus, Australian Bureau of MeteorologyResearch Centre (Australia)

C. Roy, Australian Radiation Protection andNuclear Safety Agency (Australia)

R. Rubenstein, U.S. Environmental ProtectionAgency (United States)

I. Ruppe, Bundesanstalt für Arbeitsmedizin(Germany)

M.A. Santinelli, Subsecretaria de ServiciosEducativos para el D.F. (Mexico)

G. Schauberger, Institute of Medical Physics,University of Vienna (Austria)

R. Schmidt, World Health Organization(Switzerland)

O. Schulz, Bundesamt für Strahlenschutz(Germany)

G. Seckmeyer, Fraunhofer Institute forAtmospheric Environmental Research(Germany)

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E. Simeone, NEC Italia (Italy)

P. Simon, Institut d’Aéronomie Spatiale(Belgium)

C. Sinclair, The Cancer Council Victoria(Australia)

D.H. Sliney, U.S. Army Center for HealthPromotion and Preventive Medicine (United States)

H. Staiger, Deutscher Wetterdienst(Germany)

M. Steinmetz, Bundesamt für Strahlenschutz(Germany)

C. Stick, Institut für MedizinischeKlimatologie, Kiel (Germany)

F. Tena, Facultat de Fisica, Valencia (Spain)

M. Treiliba, Latvian HydrometeorologicalAgency (Latvia)

G. Vlcek, Bundesamt für Strahlenschutz(Germany)

E. Vogel, Bundesamt für Strahlenschutz(Germany)

D.I. Wardle, Meteorological Service ofCanada, Environment Canada (Canada)

E. Weatherhead, NOAA (United States)

A. Webb, University of Manchester Instituteof Science and Technology (UnitedKingdom)

S. Wengraitis, U.S. Army Center for HealthPromotion and Preventive Medicine (UnitedStates)

U. Wester, Swedish Radiation ProtectionInstitute (Sweden)

M. Wittwer, Deutsche Krebshilfe (Germany)

L. Ylianttila, STUK-Radiation and NuclearSafety Authority (Finland)