Title: Annual Refresher Training
1Annual Refresher Training
2Training Requirements
- In order to work with radioactive material you
must be properly trained on the safe use and the
minimization of risk associated with each
isotopes. - To keep your radiation worker status, you must
have radiation safety refresher training once a
year
3Radiation is energy traveling through space, its
most familiar form is sunshine
- Cosmic Radiation high energy particles and
photons from the sun and other celestial sources - Terrestrial Radiation radioactive materials
occurring naturally in the earths crust - Internal Radiation from radioactive materials
incorporated in the human body - Inhaled Radiation primarily radon and its
progeny
4Properties of Radiation
- Radioactivity is the natural property of certain
nuclides to spontaneously emit energy, in form of
ionizing radiation, in an attempt to become more
stable. - Ionizing radiation has the ability to remove
electrons from atoms, creating ions. Ionization
is the product of negatively charged free
electrons and positively charged ionized atoms
5Ionizing Radiation
- Particles
- Alpha 2 protons 2 neutrons
- Beta electrons emitted from nucleus
- Neutrons classified by energy
- Photons
- Gamma no mass, no charge, speed of light
6Radiation Units
- Rad (radiation absorption dose) is a measure of
energy imparted to the medium - Roentgen (R) is a measure of energy imparted to
air, and the rem or dose equivalent takes into
account effects from different types of ionizing
radiation. - Rem stands for Roentgen Equivalent Man, a unit
of biological dose deposited in the body. The
number of rems of radiation is equal to the
number of rads absorbed multiplied by the
relative biological effectiveness. One rem 10
seiverts - Curie (Ci) is the unit to measure a
radioactivity, often expressed in smaller units
like thousandths (mCi) or one millionth (uCi) - One curie(Ci) 3.7 x 1010 dps (disintegrations
per second) - One millicurie(mCi) 3.7 x 107 dps 1 x 10-3
Ci - One microcurie (µCi) 3.7 x 104 dps or 2.22 106
dpm (1 x 10-6 Ci) - Becquerel (Bq) is a unit to measure a
radioactivity, 1 transformation in one second,
hence there are 3.7 x 1010 Bq in one curie
7ALARA
- Primary goal of radiation safety is to avoid any
unnecessary radiation exposure and to keep all
exposure - As Low As Reasonable Achievable
- Three mains ways to keep your doses ALARA is
- Time
- Distance
- Shielding
- Note Obtaining higher doses in order to get the
experiment done quicker is NOT reasonable
8Time, Distance, Shielding
- Time Decrease exposure time decrease the
radiation dose proportionately. - Distance The radiation dose rate varies with
the inverse square of the distance of the source.
Thus doubling distance from source will decrease
the dose by factor of four - Shielding
- Alpha is not an external hazard
- Beta stopped by ¼ inch of plexiglass, not lead
- Gamma stopped by high density materials such as
lead
9Preventing Internal Exposure
- INTERNAL RADIATION EXPOSURE CONTROLFollow the
precautions below to minimize internal radiation
exposure - Prevent absorption by changing your gloves
frequently. Avoid touching your eyes, nose or
mouth while conducting experiments. Monitor your
work area with survey meter, wash your hands, and
check your hands and lab coat with a survey
meter. - Prevent inhalation by using fume hood when you
are using any volatile sources of radioactivity. - Prevent ingestion by never eating, or drinking in
the laboratory. Never store food in refrigerators
or freezers or other areas designated for
chemical or radioactive material storage.
10Preventing Internal Exposure
- Use protective clothing. Always wear a
laboratory coat, gloves, and closed-toe-shoes
when working with unsealed radioactive materials - Avoid spreading contamination. Do not touch
telephones, light switches, faucet handles, or
doorknobs with gloved hands. - Look for contamination. Frequent monitoring of
hands, surfaces, and equipment will alert you to
contamination
11Exposure Limits
- These limits are to ensure the risks from
occupational radiation exposure levels are
indistinguishable from other risks encountered
from an average day of living - Trunk of the body 5 rem/ year
- Extremities 50 rem/year
- Lens of the Eye 15 rem/ year
- Organ dose 50 rem/ year
12Exposure Limits
- Declared Pregnant Worker
- The occupational dose level for a declared
pregnant worker is limited to 500 mrem during the
entire gestation period, or an average of 50 mrem
per month. - The pregnant worker can only be monitored if she
declares her pregnancy in writing to the
Radiation Safety Officer.
13Survey Meters
- Check battery condition needle should go to BAT
TEST line on meter - Turn large switch to the lowest scale turn on
audio switch. - Note meter background reading in a location
away from radiation source. - Place probe (window face down) about ½ inch from
surface being surveyed. - Try not to let probe touch surfaces being
checked. - Survey work area by slowly moving probe over
surfaces, listen to audible clicks from survey
meter speaker.
14Surveys
- Routine surveys of laboratory areas are the only
means to ensure a safe and contamination free
working environment - Before and after each experiment, surveys of the
radiation use area using Geiger counter or wipe
tests - Monthly wipe tests of use areas and Geiger survey
of storage area must be recorded and kept in
laboratory.
15Wipe Samples
- With a cotton wafer, wipe an area of
approximately 100cm2 (about the size of a U.S.
dollar bill). You should wipe about 1 of the
accessible surface area in hot area. - In clean areas, take wipes of frequently used
items or areas calculators, phones, door knobs,
high traffic floors, etc. - Count the wafer with at least 3 ml of safe
scintillation cocktail, along with a background
sample consisting of a new/unused, damp, cotton
wafer, in a liquid scintillation counter (set to
open or wide window). The results should be
reviewed and data taped on the appropriate lab
schematic, sign and date the form. Â
16Wipe Tests
- How do I determine if an area is contaminated?
- Note Take gloves off before entering room.
- If the open-window count exceeds 200 cpm above
background, you should recount the wipe vial
before making it public to the other users in the
room. - If result is still above 200 cpm, you must
decontaminate the area and perform another wipe
test. - Â A meter reading two times background in any part
of your lab area that has no nearby radioactive
material storage or radioactive waste storage
needs to be decontaminated. If area cannot be
cleaned after two attempts, contact Radiation
Safety officer for assistance.
17Half-life
- Half-life (T½) is the amount of time required for
radioactive material to decrease by one half. -
- Each radioisotope has a unique Half-life time
period.
18Common Radioactive Materials in Laboratories
- Phosphorus - 32 (P-32) Half life 14.29
days - Pure beta emitter Eavg 0.695 MeV max range in
air 20 feet Emax 1.71 MeV max range in
lucite .02 inch - Hazard External skin Internal Detection
Survey meter - Phosphorus 33 (P-33) Half life 25.3 days
- Pure beta emitter max range in air 20 feet
- Hazard- Slight external max range in lucite
.02 inch - Detection Survey meter
-
- Iron - 59 (Fe-59) Half life 44.5 days
- Low energy gamma X-rays Typical shielding
needed (0.5 mm of lead) - Hazard Internal organs Detection Survey
meter
19Common Radioactive Materials in Laboratories
- Iodine-125 (I-125) Half Life 60.14 days
- Low energy gamma X-rays Typical shielding
needed (0.5 mm of lead) - Hazard External Internal Detection Survey
meter - Calcium 45 (Ca-45) Half life 162.7 days
- Pure beta emitter max range in air 20 feet
- Hazard- Whole body and bone max range in lucite
.02 inch -
- Cadmium-109 (Cd-109) Half Life 462.6 days
- Gamma X-rays Typical shielding needed (0.5 mm
of lead) - Hazard External Internal Detection Survey
meter
20Radiation Spill Scenario
- Youve just spilled radioactive material on your
lab coat and arm. - Remove contaminated clothing and place them in a
plastic bag - Rinse exposed area thoroughly with soap and
water, do not scrub - Obtain medical attention if necessary
- Report the incident to your supervisor, and to
the Radiation Safety Officer
21Incidents/ Accident Response
- A Minor Incident is radioactive material has been
spilled with no personnel contamination and your
are confident in your ability to contain and
clean the spill. - Confine the spill and notify others in area
- Cover spill with absorbent paper
- Verify the isotope and estimate the activity
involved - Begin decontamination efforts, working from outer
edge of the spill in to the center - Notify your supervisor and the Radiation Safety
Officer of the incident
22Incidents/ Accident Response
- A Major incident is one where the radioactive
material has been spilled and there is some type
of personal contamination, high activity, or
large area contamination, or you just arent
confident that you can contain the material - Notify others in the are and confine the spill
and contaminated personnel - Start decontamination procedures and notify
Radiation Safety Officer as soon as possible - Clean up and decontamination will be supervised
by RSO.
23Incidents/ Accident Response
- An Emergency is a situation where radioactive
material has been spilled and the spill involves
a fire, explosion, or personnel injury - Evacuate the area and call 5-111 or 911
- In injury involved administer first aid
- Contact Radiation Safety Officer as soon as
possible
24Security
- Radioactive material must be secured from
unauthorized persons. This mean that your
radioactive material must be stored and used in a
way that prevents unauthorized persons from
gaining access to it. - Principal investigators must determine the means
used to assure security
25The End
- Youre Done! See you next year.
- And dont forget to take the mandatory quiz.