Calculation of Category 3 Radiological Thresholds

DOE-STD-1027-92

ATTACHMENT 1

Solid/Powder/Liquid

1 E-3

(All materials not listed above)

Calculation of Category 3 Radiological Thresholds

In the Senior Nuclear Managers' meeting of October 26, 1992, DOE determined that it is

reasonable to set the limit based upon the value that is accepted by the EPA for protection

of workers for planned reentry into a facility after an incident (EPA in Manual of Protective

Action Guides and Protective Actions for Nuclear Incidents, EPA 400-R-92-001) and cited

in Appendix 2A of the RadCon Manual, which is 10 rem.

DOE has chosen to use an EPA model* to calculate the threshold quantities for Category

3. The model assumes that: the distance from the point of release to the point of

exposure is 30 meters; the dose-equivalent limit is 10 rem effective whole body dose; and

there is no radioactive decay (for the sake of conservatism and simplicity). For the period

of exposure, the models used assume that persons are exposed for one day for inhalation

and direct exposure, but that persons are exposed for longer periods through the

ingestion pathway.

See Section 3.0 of this Standard for guidance on the proper use of this Table.

40 CFR 302.4 Appendix B, calculations described in User's Manual for the

Radionuclides Database Version 1.02

A-9