ML19289F879
| ML19289F879 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 06/19/1979 |
| From: | Allan J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Sniezek J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| NUDOCS 7906210012 | |
| Download: ML19289F879 (1) | |
Text
J
. MEMOR.WDUM FOR:
James H.
Sniezek, Director Division of FFMSI FROM:
James M. Allan, Director TMI Investigation Team SUBJ ECT:
EXPOSURE OF RADIATICN SURVEY INSTRUMENTS TO KNCWN XE-133 CONCENTRATIONS AT NBS We have identified, as a result of our investigative activities at TMI, the need to determine the adequacy of portable radiation survey instruments as un indicator of ga :ma exposure rates due to an ambient cloud of Xe-133.
The instruments believed to be used by the licensee to perform environmental radiation surveys were the primarily the following:
Eberline PIC-6A Eberline RO-2 Eberline E-520 (with HP-1773 probei We have sufficient RO-2s on hand to permit us to furnish two instruments for use in the exposure at NES; however, E-570s and PIC-6As will have to be obtained elsewhere (temporary loan basis) from another agency in the Washington area (perhaps NES) or from one of the Regional Offices.
The experiment itself should be designed to yield the following information:
Response in the " window open" and " window closed" positions a.
in an ambient radiation field on the order of 5-50 mR/hr.
b.
Whether accumulation by diffusion or leakage around the mR/hr window of noble gases inside the ion cha=ber appears to be a problem.
(Perhaps a long term -- an hour or more -- exposure might determine this.)
c.
The calculated beta and gamma dose rates in air in terms of mrad /hr, considering the geometry of the Xe-133 cloud need the exposure position within the cloud.
We desire to have the above information by mid-June so that it can be incorporated in the draft investigation report which is presently targeted for June 30.
Your assistance in expediting this matter is appreciated.
Jr.es M. Allan, Director TMI Investigation Team 79062100a O,
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