Release of Materials - doe-hdbk-1106-97

DOE-HDBK-1106-97

APPENDIX D

RELEASE OF MATERIALS

A. Monitoring Techniques General

Monitoring techniques for release of materials are addressed in DOE/CH-9401

(1993). The following techniques apply for G-M detectors (H-3 cannot be measured).

1. Surveys should be conducted in a low background area (background levels are

not to exceed 300 cpm; lower levels are preferable and in most cases achievable).

2. Direct measurement should be made prior to smear surveys.

3. Materials or equipment with inaccessible surface areas should be disassembled

for survey or the inaccessible areas evaluated for contamination with special

survey techniques or by review of process knowledge.

If potential for internal contamination cannot be adequately assessed,

material may not be released.

4. An audible response should be utilized as the principal indicator for initial

detection of surface radioactivity.

5. The assigned instrument/detector efficiencies should reflect a prior evaluation of

facility wastes.

Typical efficiencies for a thin-window G-M probe.

C-14, S-35 - 10%.

P-32 - 50%.