Dose Assessment - doe-std-1128-98

DOE-STD-1128-98

DAC -

hours

Air Concentration

Duration (hours)

(5.2)

DAC

Intake =

Air Concentration *

Breathing Rate * Time

(5.3)

DAC = The airborne concentration for radionuclides listed 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:

H 50

(DAC - hours) * Dose Limit

2000 DAC - hours

(5.4)

Intake* Dose Limit

H 50

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.

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