2011 Radiation Machine (xrd) User Refresher Radiation Safety Refresher for Radiation Producing Machine (xrd) Safety Conrad Sherman x9-3911 RSO/Health Physicist

2011 Radiation Machine (xrd) User Refresher

Radiation Safety Refresher for Radiation Producing Machine (xrd)

SafetyConrad Sherman x9-3911

RSO/Health Physicist

Marcus Balanky x9-5167ARSO/ Health Physicist

Vern Ares x9-5167Assistant Health Physicist

Environmental Health & SafetyRadiation Safety


Annual Refresher Training is Required• Option 1 –Challenge the test• Option 2 – review this presentation, radiation safety manual, rpm

fundamentals workbook (ucsc radiation)• Option 3 –request a class

then

• Pass the Test • Test is on e-commons• Please complete within 30 days of your last test date (if you don’t know it,

then look on e-commons, in your PI’s radiation safety folder/training is a report showing training for all users within your lab group.

Location of EHS/Radiation published materials

http://ehs.ucsc.edu/lab_research_safety/xray_safety.php


Radiation Safety


Purpose of This Class

• Annual x-ray XRD RPM users at UCSC

• Fulfill regulatory requirements

• Campus and UC Policy


Radiation Safety Fundamentals

New Radiation User

Dependent UserLearns "hands-on" skills from a

more experienced user.

Annual Refresher Training

RadioisotopeLaboratory

Safety

Sealed SourceSafety

X-rayProducingMachineSafety

You are here


Pregnancy Policy


X-ray Diffraction Safety Training

Slides modified from a class offered by John Pickering SJSU Radiation safety Officer


What are x-rays?• X-rays are photons (electromagnetic radiation) which originate in the

energy shells of an atom, as opposed to gamma rays, which are produced in the nucleus of an atom.


Visible Light


X-rays on EM spectrum


What are x-rays?• X-rays are produced when

accelerated electrons interact with a target, usually a metal absorber, or with a crystalline structure. This method of x-ray production is known as bremsstrahlung.

• The bremsstrahlung produced is proportional to the square of the energy of the accelerated electrons used to produce it, and is also proportional to the atomic number (Z) of the target (absorber).



Photon Energy and Total Power

The total powerP = V x I

As the voltage increases the penetration increasesAs the Current increases the dose rate increases


What are x-rays?• Many different types of machines produce x-rays, either

intentionally or inadvertently. Some devices that can produce x-rays are x-ray diffractometers, electron microscopes, and x-ray photoelectron spectrometers.

• X-rays can also be produced by the attenuation of beta particles emitted from radionuclides.


How X-rays are Produced

X-ray Tube

When fast-moving electrons slam into a metal object, x-rays are produced. The kinetic energy of the electron is transformed into electromagnetic energy.


Radiation Sources• X-ray diffraction is a source of very intense

radiation. • The primary beam can deliver as much as

400,000 R/minute• Collimated and filtered beams can produce

about 5,000 to 50,000 R/minute• Diffracted beams can be as high as 1

R/minute


At HIGH Doses, We KNOW At HIGH Doses, We KNOW Radiation Causes HarmRadiation Causes Harm

• High Dose effects seen in:– Radium dial painters– Early radiologists– Atomic bomb survivors– Populations near Chernobyl– Medical treatments– Criticality Accidents

• In addition to radiation sickness, increased cancer rates were also evident from high level exposures.


Ionizing Radiation

Produces damage through ionization and excitation


Bioeffects

• Somatic (body) effects of whole body irradiation can be divided into "prompt" effects and "delayed" effects.

• Prompt – effects that appear quickly

• Delayed – effects that may take years to appear

Prompt

Delayed

Diagnostic X-rayExposure


Genetic Effects• Somatic

– Damage to genetic material in the cell– May cause cell to become a cancer cell– Probability is very low at occupational

doses

• Heritable– Passed on to offspring– Observed in some animal studies

but not human


Biological Effects of Radiation

• are dependent upon:–Total energy deposited

–Distribution of deposited energy

Low dose, low-dose rate radiation exposure. The effects are in great dispute. It is thought that the effects of a protracted dose of radiation are not as great as with an acute dose because of biological repair mechanisms.


Prenatal Radiation Exposure

• Sensitivity of the unborn– Rapidly dividing cells are radiosensitive

• Potential effects– Low birth weight - (most common)– Mental retardation– Chance of childhood cancer


Bioeffects- X-rays and Skin

• Most radiation overexposures from analytical x-ray equipment are to the extremities.

• For x-rays of about 5-30 keV, irradiation of the fingers or hands does not result in significant damage to blood-forming tissue.

• At high exposures some general somatic effects to the skin can occur. Very high exposures may necessitate skin grafting or amputation of the affected extremity.

• Biological effects can be observed at 10 rem in special blood studies. Typically effects are visually observed at 50 to 100 rem.


X-Ray Burns vs. Thermal Burns

• Most nerve endings are near the surface of the skin

• High energy x-rays penetrate the outer layer of the skin that contains most of the nerve endings so one

does not feel an X-Ray burn until the damage has been done

• X-rays penetrate to the deeper, basal skin layer, damaging or killing the rapidly dividing germinal cells, that are destined to replace the outer layers


Accident Case Study• Case Study - A

radiation accident at an industrial accelerator facility

• 3MV accelerator. 40 rad/s inside victim’s shoes, 1300 rad/s to hands.

• 3 days after exposure•Note erythema and swelling

•1 month after

• Note blistering and erythema

• 2 months after


ALARAALARA

As Low As Reasonably Achievable


Dose Examples

1000 mrem SRS ANNUAL DOSE CONTROL LEVEL FOR RADIATION WORKERS - 800 mrem

AVERAGE DIAGNOSTIC NUCLEAR MEDICINE PROCEDURE - 430 mrem AVERAGE U.S. NON-OCCUPATIONAL RADIATION DOSE PER YEAR - 334 mrem AVERAGE ANNUAL DOSE FROM RADON IN THE HOME - 200 mrem AVERAGE ANNUAL DOSE TO A MEMBER OF AN AIRLINE FLIGHT CREW - 160 mrem

100 mrem AVERAGE U.S. NON-OCCUPATIONAL DOSE FOR I MONTH - 28 mrem ADDITIONAL ANNUAL BACKGROUND DOSE FROM LIVING IN A MASONRY HOME - 13 mrem

10 mrem CHEST X-RAY - 8 mrem AVERAGE U.S. BACKGROUND DOSE PER WEEK - 6 mrem ROUNDTRIP ATLANTA TO LOS ANGELES AIRLINE FLIGHT - 4 mrem

1 mrem ADDITIONAL DOSE FROM A ONE DAY VISIT IN DENVER - 1 mrem ROUNDTRIP ATLANTA TO NEW YORK AIRLINE FLIGHT - 0.4 mrem

0.1 mrem DOSE FROM SPENDING 1 HOUR IN GRAND CENTRAL STATION - 0.05 mrem ADDITIONAL DOSE FOR EACH HOUR SPENT IN DENVER - 0.05 mrem DOSE FROM SPENDING 1 HOUR AT THE STATUE OF LIBERTY - 0.04 mrem

0.01 mrem AVERAGE DOSE FROM A SMOKE DETECTOR IN THE HOME - 0.01 mrem DOSE FROM K-40 IN 1 BANANA - 0.007 mrem

Dose around our XRD machines in room 284: 0.015 mrem/hr


1 Table 9. Estimated Loss of Life Expectancy Due to

Various Causes

Cause Days of Life Lost Cause Days of Life Lost

Cigarette smoking (male) 2250 Job with radiation exposure 40

Heart disease 2100 Falls 39

Being 30% overweight 1300 Accidents to Pedestrians 37

Being a coal miner 1100 Safest job (accidents) 30

Cancer 980 Fire (burns) 27

Being 20% Overweight 900 Generation of energy 24

Cigarette smoking (female) 800 Illicit drugs (U.S. average) 18

Stroke 520 Poison (solid, liquid) 17

Living in unfavorable state 500 Suffocation 13

Cigar smoking 330 Firearms accidents 11

Dangerous job (accidents) 300 Natural radiation 8

Pipe smoking 220 Poisonous gases 7

Increasing food intake 100 calories/day

210 Medical X rays 6

Motor vehicle accidents 207 Coffee 6

Pneumonia (influenza) 141 Oral contraceptives 5

Alcohol (U.S. average) 130 Accidents to bicycles 5

Accidents in home 95 All catastrophes combined 3.5

Suicide 95 Diet drinks 2

Diabetes 95 Reactor accidents (UCS) 2*

Being murdered (homicide) 90 Reactor accidents (NRC) 0.02*

Legal drug misuse 90 PAP test -4

Average job (accidents) 74 Smoke alarm in home -10

Drowning 41 Air bags in car -50

Mobile coronary care units -125


Documenting Surveys

• surveys must be documented• Record the following:

– date performed– area(s) surveyed (a map helps!)– results– identity of surveyor– instrument used– action taken if problem is found


Engineering Controls

• Interlocks – never bypass interlocks or

other safety devices

• Warning Lights – know the beam status

whenever working with XRD

• Shielding

• Locked doors


Failsafe Equipment

• Getting better

• High reliability

• Still see reports of failures

• Always use survey meter


Precautions

• If you rely on an interlock to turn off the beam for the purposes of accessing the sample area, you must confirm the beam is off using a calibrated survey meter before your put your hand in the cabinet enclosure.


Interlock as on-off switch

• Never


Key Control

• Who has keys

• Special alignment bypass keys

• Never Left Out, always locked in case/cabinet

• Only PI and Lab Manager hold access to bypass keys


Access

• You are required to secure access to your RPMs.

• Rooms where RPMs are present must be kept locked if the machine is left unattended.

• If your RPM is equipped with a key interlock then the key must be removed when the machine is not being used.


New MachineMoving Machine?

Decommissioning?

• Call RSO


Problems with equipment• If there are any questions or concerns

about the functioning of an XRD unit, it must be taken out of service immediately and reported to the unit supervisor.

[Be aware that shutter mechanisms can fail. Warning lights can fail.]


General Methods of Protection

• Time

• Distance

• Shielding


Verify you have viewed this powerpoint

• Logon to ecommons RAD SAF Exams and take 2011 RPM XRD Refresher


Test• To receive credit for this online training course,

you must complete the exam and receive a score of 80% or greater.

• You may take test up to 3 times• Some questions have multiple correct answers• You can review answers at end of each test• Each test is a new set of questions randomized

from test bank• If you do not pass, we will go over failed

questions with you


Test Completion

• Online e-commons RADSAFE EXAMS

• PAPER PRINT A COPY OF TEST,

• Send to ehs trailer


Verify you have viewed this powerpoint

• Logon to ecommons RAD SAF Exams and take 2011 rpm machine user Refresher quiz

e-commons portal (https://ecommons.ucsc.edu/xsl-portal)


We’re there for you.Environmental Health & Safety x9-2553

– Conrad Sherman x9-3911– RSO/Health Physicist

– Marcus Balanky x9-5167– ARSO/ Health Physicist

– Vern Ares x9-5167– Assistant Health Physicist

• Environmental Health & Safety• Radiation Safety• (831) 459-3911

Web site http://www.ehs.ucsc.edu/

Documents

2011 Radiation Machine (xrd) User Refresher Radiation Safety Refresher for Radiation Producing Machine (xrd) Safety Conrad Sherman x9-3911 RSO/Health Physicist