Some observations obtained from a nation-wide in vivo counting service

Conference · Sat Jan 01 04:00:00 EST 1972

OSTI ID:4311552

Hegelson, G L; Pollard, D E; Willis, C A ^[1]

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1. ed.

From 3rd Health Physics Society midyear topical symposium; Los Angeles, California, USA (29 Jan 1969). See CONF-690103P2. Since most redioisotopes encountered in the nuclear industry are insoluble, in vivo counting provides one of the best methods for determining internal burdens of many radioisotopes. This papcr discusses findings from approximately 7000 counts during the first three years of a nation-wide mobile in vivo counting service. /sup 60/Co the most frcquently observed contaminant, will probably contribute the most lung exposure. Its effective half-life is generally about one to two years. /sup 65/Zn is present in people working at reactors where Admiralty Metal is used. It tends to mask other nuclides such as /sup 60/Co and causes othcr operational problems such as high dose rates from waste containers. Using an 8 x 0.5 inch NaI(Tl) detector in a shadow shield whole-body counter the authors have been suceessful in routinely measuring as low as 20% of the maximum permissible lung burden (MPLB) of /sup 235/U in a 40 minute count. If the true lung burden is 0.245 mg of /sup 235/U, one MPLB at 93% enrichment. the probability is 90% that in any one measurement the observed activity will be 0.245 plus or minus 0.088 mg. Most industries have an excellent safety record, however, a few have significant internal dose problems. The in vivo records have proven very useful in discovering trends in plant contamination status, boosting sagging employee morale, and in proving to regulatory agencies that the latest techniques are used for estimating internal dose. (auth)

• Research Organization: Helgeson Nuclear Services, Inc., Pleasanton, CA
• NSA Number: NSA-29-029845
• OSTI ID: 4311552
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*COBALT 60-- RETENTION
*NUCLEAR FACILITIES-- PERSONNEL MONITORING
*PERSONNEL MONITORING-- WHOLE-BODY COUNTING
*RADIATION DOSES-- DATA COMPILATION
*URANIUM 235-- RETENTION
*ZINC 65-- RETENTION
ENVIRONMENT
INTERNAL IRRADIATION
LUNGS
N44300 --Environmental & Earth Sciences--Radioactivity Monitoring & Transport
N48610* --Life Sciences--Radionuclide Effects (Internal Source)--Man
PERSONNEL
RADIATION MONITORING
RADIONUCLIDE KINETICS
UPTAKE NUCLEAR FACILITIES