Beta/Gamma Direct Monitoring - doe-hdbk-1106-97

DOE-HDBK-1106-97

Lesson Plan

Instructor's Notes

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%.

Results: If surveys indicate

Beta/Gamma Direct Monitoring

1. Window: Use a thin-window probe, detector window

(refer to 10 CFR 835

thickness (mylar) should not be more than 2.0 mg/cm2.

Appendix D for release from

controlled areas or DOE

2. Scanning: Scan the surface; in most cases, scanning

5400.5, Ch.2, for unrestricted

will cover nearly 100 percent of accessible surfaces.

release), the material should

not be released. Prior to

3. Distance: Maintain detector window no more than inch

release, contamination levels

from surface.

must be less than appropriate

values and should be reduced

4. Speed: The number of counts produced in the detector

as low as reasonably

is inversely proportional to the scanning speed.

achievable.

5. Audio: If at any point a perceivable audible or visual

response is detected, perform a stationary evaluation

of count rate.

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