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Flashcards in Radiation Protection Deck (17)
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1
Q

Which agency oversees materials produced by a nuclear reactor?

A

NRC

2
Q

Which agency oversees radiopharmaceuticals?

A

FDA

3
Q

Which agency oversees linear accelerators?

A

State agency

4
Q

What are the dose limits for the following structures per year for general population?

1) Total body
2) Lens
3) Orgnas

A

1) 5 mSv
2) 15 mSv
3) 50 mSv

5
Q

What are the dose limits for radiation workers:

1) Total body
2) Lens
3) Organs

A

Multiply the genpop x 10:

1) 50 mSv
2) 150 mSv
3) 500 mSv

6
Q

What is the dose limit for an undeclared pregnancy? Declared?

A

5 mSv

0.5 mSv/mo (~5 total)

7
Q

What is the Workload (W) factor?

A

Beam-on time essentially. This is the weekly dose delivered at 1 m from the source (cGy/week at 1m)

8
Q

What is the Use (U) factor?

A

Proportion of time that a source is directed at a particular barrier (e.g. half the time the beam is on it’s directed at the floor, so the U for the floor is 0.5)

9
Q

What is the Occupancy (T) factor?

A

fraction of operating time the area is occupied. E.g. offices or workstations = 1, restrooms = 1/4, waiting rooms = 1/8 etc.

10
Q

What is the transmission factor (B) of a barrier?

A

It is the thickness of a barrier required to reduce a radiation level to within an acceptable standard (P).

11
Q

What is the equation for B?

A

B= P x d^2/WUT

where P = the permissible dose equivalent of an area

12
Q

What are the purposes of secondary barriers?

A

To protect against scatter and leakage

13
Q

How thick is a primary barrier typically? a secondary?

A
Primary = 8.6 ft
Secondary = 4.3 ft
14
Q

What is the U of a secondary barrier?

A

1, always 1 (it’s scatter, so any time the beam is on it’s getting hit)

15
Q

How much leakage is allowed from treatment heads?

A

<0.1% of the treatment beam

16
Q

What exposure is allowable before release of a brachytherapy patient?

A

5 mSv (0.5 rem); instructions needed for 1 mSv (0.1 rem)

17
Q

What are the requirements for a medical misadministration event?

A

Wrong person, wrong site, or wrong dose (50% for single fraction or 20% total dose)