UMB Initial Radiation Safety Training (RST)
1. 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
2. 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
3. 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
4. The first steps in ordering radioactive material are to:
Answer:
Call vendor and order product
Ensure that isotope is listed on authorization and that possession limits are not exceeded
Obtain a control number from the Radiation Safety Office
Both b. and c.
5. A charged particle (beta or alpha) can interact directly with matter by:
Answer:
Ionization and excitation
Compton scattering
Pair production
The photoelectric effect
6. The primary difference between gamma rays and x-rays is:
Answer:
Gamma rays are higher in energy
Gamma rays originate in the nucleus, X-rays originate in the electron shells
X-rays are used in medical applications
X-rays originate in the nucleus, gamma rays originate in the electron shells
7. When first using a radiation detection instrument, you should:
Answer:
Familiarize yourself with the instruments operation
Check the detector response to radiation using a known source of radiation
Perform a battery check and check instrument calibration
All of the above
8. The theory that small amounts of radiation are necessary for good health is:
Answer:
A lie put out by the food irradiation industry
True only if it is alpha radiation
True only if it is x and/or gamma radiation
Radiation hormesis
9. Which of the following radionuclides has 15 protons and 18 neutrons in the nucleus of it's atoms?
Answer:
Phosphorous-32
Phosphorous-33
Silicon-32
Sulphur-35
10. The most radiosensitive mammalian organs are:
Answer:
Blood forming organs
Digestive organs
Nerve cells
Calcified bone
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. Medical procedures using radiation can include which of the following:
Answer:
X-rays needed for diagnostics
Nuclear medicine procedures
Radiation oncology procedures
All of the above
13. The radiosensitivity of the digestive tract would be considered:
Answer:
Radiosensitive
Relatively radiosensitive
Moderately radiosensitive
Extremely radiosensitive
14. Delayed effects of radiation exposure include:
Answer:
Tissue effects
Life span shortening
Carcinogenesis
All of the above
15. 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
16. 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
17. 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
18. When deciding which liquid scintillation cocktail to use, you should:
Answer:
Use any hazardous or non-hazardous liquid scintillation cocktail
Preferably use only non-EPA regulated cocktail
Check with EHS to ensure your choice of liquid scintillation cocktails is not regulated
Both b. and c
19. The half life of P-32 is approximately 14 days, if you start with 1000 uCi, after 28 days how much P-32 would remain?
Answer:
1000 uCi
500 uCi
250 uCi
None
20. Which of the following must be posted in a Radioactive Material lab:
Answer:
Notice to Employees
Radiation Emergency Procedures
Caution Radioactive Material sign
All of the above
21. The Geiger-Mueller region differs from the other voltage regions in that:
Answer:
It has the highest voltage of all the regions
It has the highest efficiency of all the regions
It does not distinguish between particles of different energies
All of the above
22. 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%
23. 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
24. What is the best way to prevent internal exposure?
Answer:
Do not eat, drink or smoke in the laboratory
Use a fume hood when working with volatile I-25
Ensure you wear protective clothing when working with radioactive material
All of the above
25. 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
26. 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
27. A sample of Phosphorus-32 has an initial activity of 10 mCi. How much radioactive material is left after 42 days later (P-32 half-life = 14.28 days):
Answer:
0.625 mCi
1.300 mCi
2.500 mCi
5.000 mCi
28. One of the basic methods to control radioactive contamination and to prevent internal radiation exposure is:
Answer:
Proper use of time, distance and shielding
The use of remote handling devices (such as forceps)
Monitoring and surveying of the work area
None of the above
29. The calibration date of the survey meter can be located on:
Answer:
The calibration sticker present on the meter
The calibration certificate that accompanies the meter upon calibration
None of the above
Both a. and b.
30. The Rem is:
Answer:
The unit of dose equivalent that is equal to the dose in rad times the quality factor
A unit of exposure to x or gamma radiation based on the ionizations that these radiations produce in air
A unit of absorbed dose for any ionizing radiation that is equal to 100 ergs of absorbed energy per gram of substance
None of the above
31. Beta particles have a spectrum of energies because:
Answer:
The beta particle is emitted from the nucleus of the atom
The decay product, beta particle and antineutrino are created together and must share the decay energy
The proton that is created absorbs some of the decay energy
The decay products must conserve charge
32. 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
33. Dry solid waste can contain:
Answer:
Syringes
Surgical instruments
Gloves
Organic liquids
34. When should a urine analysis be performed?
Answer:
When you have worked with volatile I-125
When you work with a large amount of Tritium
When you are involved in a major spill or accident
Both b. and c.
35. The Radiation Safety Office must be contacted in the following situations:
Answer:
Prior to ordering radioactive material from a vendor
Prior to transferring radioactive material to another authorized user and/or receiving radioactive material from an authorized user
Prior to any changes involving authorization (i.e. rooms used, protocols)
All of the above
36. 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
37. A major concern when selecting shielding for high energy beta emitters is:
Answer:
Generation of secondary x-rays from bremsstrahlung radiation
Making the shielding thick enough to prevent backscatter from occurring
Shielding the neutrons that will be released as the betas interact with the shielding
None of the above
38. A strand break in the DNA, resulting from the chemical reaction of free radicals attacking a DNA sugar, is an example of what kind of radiation induced biological effect:
Answer:
Unidirectional
Direct
Indirect
None of the above
39. 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)
40. Low energy beta emitters, such as H-3 or C-14, are best detected during a survey for removable contamination by using:
Answer:
A GM thin-window detector
A sodium iodide (NaI) detector
A liquid scintillation counter (LSC)
None of the above
41. The Hazardous Waste Division of EHS:
Answer:
Charges for all radioactive waste to be removed from your laboratory
Will not provide laboratories with any radioactive waste containers
Will not remove radioactive waste directly from the laboratory
Requests that Authorized Users utilize non-hazardous scintillation cocktails in their research
42. 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
43. All of the following should be worn to prevent absorption of radioactive material through the skin except?
Answer:
A lab coat
Protective eye wear
Sandal with no socks
Gloves
44. A bioassay is a measurement used to determine:
Answer:
The extent of damage caused by exposure to an unknown source of radiation
The presence of radioactive material in the body
The current physical conditioning of the body
The length of time it will take for the body to repair damage caused by exposure to ionizing radiation
45. 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
46. 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
47. An ALARA program (As Low As Reasonably Achievable) is intended to:
Answer:
Reduce the amount of radioactive material used at a single location
Reduce the level of radiation exposure that individuals receive
Reduce the quantity of radioactive waste that is generated from an experiment
None of the above
48. 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
49. 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
50. 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.
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