3X background decision level

[William McCabe <WMCCABE@tnrcc.state.tx.us>]

Can anyone provide me with the details/basis for the thumbrule or
practice of using 3 times (or sometimes 2 times) background as a
detection (or decision) limit for portable survey instruments?

Thanks in advance.

- Will McCabe


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William J. McCabe, NRRPT, CQA
Health Physicist, MC-131
Texas Natural Resource Conservation Commission
P.O. Box 13087
Austin, Texas  78711-3087
wmccabe@tnrcc.state.tx.us
(512) 239-2252     fax: (512)239-6362
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