Generic Objectives

Question 1

Define Stochastic health effects

Answer 1

Randomly occurring health effects for which the probability of the effect occurring varies linearly with dose and has no threshold.
Stochastic effects deal with the probability of occurrence; not with the severity.
Example: The annual limit (5 Rem) for uniform irradiation of the whole body is a limit set to reduce the probability of a stoicastic health effect.

Question 2

Define Non-Stochastic health effects

Answer 2

Health effects in which the severity of the effect varies with dose and for which a threshold is believed to exist.
Example: An eye dose equivalent of 15 Rem would be a non-stochastic limit to prevent a health effect (cataracts).

Question 3

Define Annual Limit on Intake (ALI)

Answer 3

The derived limit for the amount of radioactive material taken into the body of an adult worker by inhalation or ingestion in a year.
Based on 5Rem stochastic or 50Rem non-stochastic CDE.
1 ALI = 5 Rem

Question 4

Define Derived Air Concentration (DAC)

Answer 4

The concentration of a given radionuclide in air which, if breathed by the reference man for a working year of 2000 hours under condition of light work, results in an intake of one ALI.
2000 DAC-hours = 1 ALI

Question 5

Describe the relationship between the Annual Limit on Intake (ALI) and the Derived Air Concentration (DAC)

Answer 5

DACs are not limits, but are used as guidelines to prevent intakes from exceeding ALIs.
5000 mRem = 1 ALI = 2000 DAC-hours

Question 6

State the major concerns of the plant ALARA program.

Answer 6

1. All work requiring RWP is reviewed before a job for opportunities to reduce or minimize dose. This includes Design Change Packages.
2. Work is reviewed during and after the job to document lessons learned and suggest improvements to reduce dose for future jobs.

Question 7

What is the significance of 30 cm designation in a dose rate?

Answer 7

A dose rate at 30 cm from the source is considered a general area dose rate.