UMB Initial Radiation Safety Training (RST)
1. Occupational exposure to radiation is limited to 5 REM for the whole body and 50 REM for the extremities. Upon diagnosis of a brain tumor, your doctor recommends the use of the gamma knife for treatment. Your medical treatment will be limited to:
Answer:
50.0 REM because the head is an extremity
5.0 REM because the head is part of the whole body
No limit because it is a medical procedure
100 REM because it is a medical procedure
2. Eating, smoking, drinking, or the storage of food, beverages, and tobacco in radioactive materials areas is prohibited because:
Answer:
Laboratory cleanliness is easier to maintain
Radiation protection organizations enjoy making people uncomfortable
The radiation causes food to spoil rapidly
It reduces the possibility of internal contamination
3. Before sending in a request to have radioactive animal waste removed from your laboratory, you should:
Answer:
Double bag the animal carcass and place it into a freezer
Label the bag with isotope, activity, date, and authorized user name
Call EHS for assistance if you have questions
All of the above
4. Written notification must be provided to the Radiation Safety Office:
Answer:
When an authorized user leaves the University
When an additional room is needed for radioactive material work
When vacating a room where radioactive material was used
All of the above
5. When do you need to take precautions for possible external exposure?
Answer:
When working with a low energy beta emitter like C-14
When working with a gamma emitter like Cr-51
When working with a high energy beta emitter like P-32
Both b. and c.
6. Which of the following items should not be placed in a radioactive waste container:
Answer:
Contaminated lead shielding
Sharps or needles that have not been placed into a sealed sharps container
Waste materials that are known to be non-radioactive
All of the above
7. What type of shielding is required for a low beta energy isotope like H-3?
Answer:
1 cm of plexiglas
0.02 mm of lead
5 cm of concrete
None of the above
8. Which of the following are true statements:
Answer:
The only isotopes that can be commingled into the same waste container without approval from EHS are C-14 and H-3
Animals injected with radioactive materials are not regulated for their radioactive properties
All scintillation cocktails are non-hazardous
Once the original source vials are emptied of the radioactive materials they can be disposed in the regular trash
9. Low energy gamma emitters, such as I-125, are best detected during a survey for fixed contamination by using:
Answer:
A GM thin-window detector
A sodium iodide (NaI) detector
A liquid scintillation counter
None of the above
10. An individual who is going to pick up a shipment of radioactive material from the Radiation Safety Office should:
Answer:
Have their assigned bar code ID
Have their photo ID
Be wearing their assigned whole body dosimeter
All of the above
11. If you have a source of radiation which emits ONLY high energy beta radiation e.g. P-32, what is the most appropriate shielding material to use:
Answer:
A container of iron or lead
A container of Plexiglas
A container of thin leaded glass
A container of lead inside a container of Plexiglas
12. The inverse square rule can be used to:
Answer:
Determine the level of exposure at a given distance from a point source
Determine the level of radioactivity (mCi) in a point source
Determine the decay rate of a specific isotope
None of the above
13. Radioactive material must be secured against unauthorized access or removal:
Answer:
Only when an authorized person is handling the material
Any time the material is in storage, or not under the direct control of an authorized person
When the level of radioactivity is less than 1 mCi
None of the above
14. The most radiosensitive mammalian organs are:
Answer:
Blood forming organs
Digestive organs
Nerve cells
Calcified bone
15. A sewer disposal permit authorizes the disposal of the following via the sanitary sewer:
Answer:
Hazardous materials
Alpha emitters
Any isotope and quantity
Only the isotopes and quantities specified on the sewer permit
16. The purpose of the UMB Radiation Safety Program is to:
Answer:
Burden the user with excessive regulations
Encourage the use of radioactive material in clinical and research activities
Maintain exposures of personnel to ionizing radiation from radioactive materials and radiation producing devices as low as reasonably achievable
All of the above
17. The primary hazard from an alpha emitter is:
Answer:
An internal exposure upon intake of the material into the body
An external exposure of the skin
An external exposure to the thyroid
None of the above
18. When estimating the activity of radioactive waste you should:
Answer:
Estimate the activity as close as possible to the actual activity of the waste in the container, while still assuring that you did not underestimate
Estimate the activity way below the actual activity
Give every container 100uCi activity
None of the above
19. The millicurie is a:
Answer:
Unit of radioactivity that equals 1 disintegration per second
Unit of radioactivity that equals 2.22E6 disintegrations per minute
Unit of radioactivity that equals 1 disintegration per minute
Unit of radioactivity that equals 2.22E9 disintegrations per minute
20. Which of the following is NOT a type of detector:
Answer:
Ion chamber
G-M counter
NaI
HVL
21. A wipe sample of your radioactive work area measures 100 cps (counts per sec) above background on your portable GM survey meter. If the efficiency of the detector for the nuclide of interest is 5%, how much activity (in dpm) is really present?
Answer:
200 dpm
20000 dpm
1200 dpm
120000 dpm
22. The radioactive waste log sheet needs to be filled out:
Answer:
Only after the container is full and going to be disposed of
As soon as the first radioactive material goes into the container and every addition of radioactive waste thereafter
Never needs to be filled out
All the above
23. What should you always do with used radioactive needles?
Answer:
Recap the needle
Dispose of the needle in a radioactive waste box
Dispose of the needle in a radioactive sharps container
None of the above
24. During a survey with a GM detector, the probe should be held:
Answer:
At least 6 inches away from the surface while it is rapidly passed back and forth
At contact with the surface while moving slowly
Near contact with the surface while moving slowly
None of the above
25. The maximum range of a beta particle in air is determined by:
Answer:
The activity of the isotope
The half-life of the radioactive atom
The energy of the beta particle
All of the above
26. Which radiation is the least penetrating:
Answer:
Alpha
Beta
Gamma
X-ray
27. The half-life of a radioactive element is:
Answer:
The length of time it takes to decay to background levels
A unit of radioactivity that equals 2.22E6 disintegrations per minute
The length of time it takes for one-half of the atoms to decay
None of the above
28. What do you need to do to become a declared pregnant worker?
Answer:
You just need to be a registered radiation worker
You need to declare in writing to the RSO that you are pregnant
Tell you supervisor and have him/her notify the RSO
All of the above
29. All radioactive waste containers should be labeled with:
Answer:
The isotope and activity
The chemical composition of liquids if the waste container is for liquid radioactive or scintillation vial waste
The date that the isotope and activity were assayed
All of the above
30. During a spill of radioactive material, decontamination should be performed in the following manner:
Answer:
Facility, Equipment, Personnel
Equipment, Facility, Personnel
Personnel, Facility, Equipment
Only need to clean spill and not worry about additional items being contaminated
31. A charged particle (beta or alpha) can interact directly with matter by:
Answer:
Ionization and excitation
Compton scattering
Pair production
The photoelectric effect
32. Radioactive materials Receipt/Use/Disposal forms issued by the Radiation Safety Office with every radioisotope delivered to the authorized user should be:
Answer:
Filled out each time material is withdrawn from the stock vial
Stored in the laboratory's radiation safety records
Returned to the Radiation Safety Office when the isotope is expended, transferred and/or disposed of as waste
All of the above
33. A radioactive source is measured at 32 mrem/hr at one meter. What would the exposure rate be at 10 cm:
Answer:
0.32 mrem/hr
3.2 mrem/hr
320 mrem/hr
3200 mrem/hr
34. To prevent the spread of contamination after a minor spill, a person should immediately:
Answer:
Take off their lab coat and gloves
Exit the area and call Radiation Safety for assistance
Cover the spill with absorbent material
Wash the bench top after working and before conducting a contamination check
35. Ion chambers are useful for:
Answer:
Detecting contamination on a given surface
Locating a missing gamma emitting source
Determining exposure risks from unknown sources
None of the above
36. Detection efficiency is calculated by:
Answer:
Dividing the number of microcuries by the decay constant (0.693/T)
Dividing the number of counts by the number of actual disintegrations
Dividing the atomic weight of an atom by its Z number
None of the above
37. Contamination surveys (wipe tests) must be recorded as follows:
Answer:
Cpm
Wipe tests must be performed but not documented
Dpm
mR/hr
38. How long should radioactive materials users keep dosimetry exposure reports on file?
Answer:
10 years
5 years
2 years
1 year
39. The annual extremity dose limit for radiation workers in the Maryland regulations is:
Answer:
5 rem
7.5 rem
12 rem
50 rem
40. The annual whole body dose limit for a member of the public at large is:
Answer:
0.1 rem
0.3 rem
5.0 rem
50 rem.
41. It is acceptable to wear another persons dosimeter when:
Answer:
They work in the same area and handle the same radioactive material
They are on vacation and will not need their dosimeter
You should never wear another person’s dosimeter
None of the above
42. The least radiosensitive mammalian cells are:
Answer:
Nerve cells
Germ cells
White blood cells
Endothelial cells
43. Contamination should be measured in what units?
Answer:
Disintegrations per minute (dpm) per 100 square centimeters
Counts per minute (cpm) per 100 square centimeters
Disintegrations per minute (dpm)
Millicuries (mCi)
44. A strand break in the DNA, resulting from the initial ionizing event in the molecule, is an example of what kind of biological effect:
Answer:
Unidirectional
Direct
Indirect
None of the above
45. A scintillation detector operates by:
Answer:
Converting ionizing radiation to UV photons
Collecting the charge created by ionizations in the wall of the probe
Collecting the charge created by ionization in the gas contained in the probe
All of the above
46. How long can you work in a 200 mR/hr radiation field and limit your exposure to 50 mR:
Answer:
15 minutes
4 hours
30 minutes
None of the above
47. Dose Equivalent (DE), Effective Dose Equivalent (EDE), Committed Dose Equivalent (CDE), Committed Effective Dose Equivalent (CEDE), and Total Effective Dose Equivalent (TEDE) are expressed in units of:
Answer:
Grays (Gy) and Sieverts (Sv)
Roentgen or ergs
Rads and coulombs
Sieverts (Sv) or REM
48. If you pass a beam of x-rays through 3 half value layers (HVLs) of a material, what will be the resulting beam intensity?
Answer:
97%
33.30%
12.50%
3%
49. If not properly calibrated, a liquid scintillation counter (LSC) will usually report results in:
Answer:
Disintegrations per minute (dpm)
Counts per minute (cpm)
Millicuries (mCi)
None of the above
50. Items that have been labeled with a Caution - Radioactive Material sign can be disposed of as normal trash when:
Answer:
They have been surveyed and found to be free of contamination
The label has been defaced or removed
Both a. and b.
None of the above.
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