Practice Exam #3 23-35

Question 1

Reason for performing general area dose rates?

Answer 1

1. Determining stay times
2. Establishing exposure controls
3. Deriving dose estimates when performing job planning

Question 2

A general area dose rate is measured at what distance from the radiation source?

Answer 2

30cm away

Question 3

A dose rate taken by placing the detector housing against the radiation source is called a contact dose rate. True or False?

Answer 3

True

Question 4

Contact dose rates are important for which of the following reasons?

Answer 4

Establishing expected exposure rate to extremities

Question 5

Methods that can be used to reduce exposure to radiation.

Answer 5

1. Install temporary shielding to reduce (attenuate) the dose rates in the area.
2. Use long handle tools to increase the distance from the source.
3. Use robots to perform the activity allowing the workers to avoid the exposure

Question 6

These are the following methods to lower dose to workers?

Answer 6

1. Flush the system to remove radiation sources
2. Decontaminate the system to remove activity
3. Use HEPA ventilation units to remove airborne radioactivity

Question 7

When Cobalt 59, an isotope in stellite, is subjected to a neutron flux in the reactor core, it forms which of the following radioactive isotopes?

Answer 7

Co-60

Question 8

Where inside the primary system in a Pressurized Water Reactor, PWR, can stellite be found?

Answer 8

Valve seats

Question 9

What is the best definition for loose contamination?

Answer 9

Radioactive surface contamination that is easily transferred to other personnel or equipment through normal contact

Question 10

The standard technique for measuring loose surface contamination is by the use of a cloth smear taken over what surface area?

Answer 10

100 cm2

Question 11

When using the survey method called frisking, you are able to take a direct measurement of the surface which includes both fixed and removable contamination. True or False?

Answer 11

True

Question 12

Which of the following statements best describes effective half-life?

Answer 12

The amount of time it takes for the activity of a radionuclide in the body to be half of its original value as result of radioactive decay and biological elimination.

Question 13

The Relative Biological Effectiveness, RBE, of radiation is the same for gamma, neutron and alpha exposure. True or False?

Answer 13

False