Dose Assessment

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

determined to be inadequate or nonrepresentative. Air sample data can be used to calculate

an exposure to airborne material either in an in terms of DAC-hours or potential

radioactivity intake as follows:

Air Concentration

DAC

- hours

Duration

(hours)

(5.2)

DAC

Intake =

Air Concentration *

Breathing Rate *

Time

(5.3)

DAC = The airborne concentration for radionuclides listed in an in Appendix A of 10 CFR

835, taking into consideration the Clearance Class (D/W/Y) expressed in :ci/mL or Bq/m3

Air concentration = airborne radioactivity in units of :ci/mL or Bq/m3

If air sample results are representative of air breathed by individuals, then doses can be

calculated using the 5-rem stochastic limit for CEDE (HE,50) or the 50-rem nonstochastic

limit for committed tissue dose equivalent (HT,50) and the respective stochastic or

nonstochastic DAC or ALI conversion factor, as shown below:

Dose

Limit

(DAC - hours) *

H 50

2000 DAC - hours

(5.4)

Dose Limit

H 50

Intake*

ALI

(5.5)

If respiratory protection is worn by workers, the appropriate respirator protection factor may

be applied to the above calculations (i.e., dividing the calculated result by the protection

factor.)

General air sampling programs should be augmented by breathing zone sampling when air

concentrations to which individuals are exposed might be highly variable. Breathing zone

sampling may include both fixed-location and personal (lapel) air samplers. Personal air

samples are more likely to be representative of actual exposure conditions than are samples

collected at fixed locations, and can be particularly useful for assessing potential intakes

involving short-term exposure to well-monitored air concentrations.

5.8 DOSE ASSESSMENT

Dose assessment involves collecting and analyzing information concerning a potential intake and

developing a conclusion regarding the magnitude of intake and its associated committed dose

equivalents. Dose assessments are conducted by investigating the nature of a potential intake and by

analyzing bioassay measurement results or other pertinent data. Biokinetic models are used in an in

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