ML20034D213
| ML20034D213 | |
| Person / Time | |
|---|---|
| Issue date: | 11/14/1991 |
| From: | Cunningham R NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | Lieberman J NRC OFFICE OF ENFORCEMENT (OE) |
| Shared Package | |
| ML20034D215 | List:
|
| References | |
| FRN-57FR56287, RULE-PR-31, RULE-PR-32 AD82-1-005, AD82-1-5, NUDOCS 9112130021 | |
| Download: ML20034D213 (1) | |
Text
._
D N G,O/h d
'l MEMORANDUM FOR: James P-berman;. Director.
(3' gg.4 Office d Enforcement NOV 14 L /
g i
a FROM:
~ Richard E. Cunningham, Director 1
Division of Industrial and i
Medical: Nuclear Safety, NMSS l
SUBJECT:
OCTOBER 23, 1991, PROPOSED RULEMAKING CONCERNING THE ACCESSIBLE AIR GAP FOR GENERALLY LICENSED DEVICES This refers to your October 28, 1991, memorandum requesting our views on your l
approach. We agree with your proposed changes to the enforcement policy if i
the air gap rule becomes final.
Although the 125 mrem /hr dose rate appears high, the calculations of annual dose are based on normal conditions of use. Actual exposure of employees inside the gap should be infrequent and under unusual circumstances. The.125 mrem /hr dose rate.was. selected on the basis that one hour per calendar quarter represented an upper limit of time that individuals may routinely spend performing maintenance within tanks and product carriers monitored by gauges-with large air gaps. The rulemaking is based on our concern that:if.the gap is large and the dose rate is higher than 125 mrem /hr, then the probability
{
of exposure in excess of 500 mrem /yr becomes too high.
j The Atomic Energy Commission (AEC) staff adopted the 500 mrem /yr criteria based on a safety assessment of an optimized and justifiable _. exposure _that' users of generally licensed devices could be permitted-to receive under-ordinary' circumstances. This was based, in part, on establishing a limit i
that would not require radiation monitoring or posting of areas, and that the device could' safely be used by minimally trained persons. The AEC did not need to make the decision as to whether the general licensed employee was a radiation worker because exposures were believed to be within the j
limits expected for the public at the time.
- i The Commission has1 requested NMSS to further examine the impact and benefits i
of changing the criteria from 500 to 100 mrem /yr. Changes in the design basis could directly affect about 16,000 general licenses under NRC jurisdication
}
and possibly require a large number to become specific licensees.. Please.
q note that the calculated exposures are to occupationally exposed employees of the general licensee. Thus the 100 mrem /yr limit for merrbers of the general public may not be applicable to such wprkers.
j
/S/
'I Richard E. Cunningham, Director Division of Industrial and Medical Nuclear Safety, NMSS DISTRIBUTION NMSS #9100584
%'&y*yn""l m _
5Baggett JEGlenn JGreeves RECunningham CEStep Hester CJenkins
.IMAB r/f IMAB r/f/
SSS. Staff l
NMSS Dir. Off. r.f IMNS Central File NRC File Center i
- See previous concurrence j
i DD/ M 'h...:D/IMftS___,
0FC:
IMAB
- IMAB j
f L.....+.
43
.,.jg...........................
q
......*....fs......
y NAME: SLBag#tt/kj :' Qenn: preeves:
urfningham
]
DATE5 55f f9k liff9515ff9[
15ffbfh[
o 4
0FFICIAL RECORD COPY LIEBERMAN
.