Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
SSINS: 6820
Accession No:
7908130463
UNITED STATES
NUCLEAR REGULATORY COMMISSION
WASHINGTON, D. C. 20555
September 5, 1979
IE Bulletin No. 79-22
POSSIBLE LEAKAGE OF TUBES OF TRITIUM GAS USED IN TIMEPIECES FOR LUMINOSITY
Description of Circumstances:
In June and July 1979, inspections were performed by the Arizona Atomic
Energy Commission with the assistance of the Nuclear Regulatory Commission
at American Atomics Corporation, Tuscon, Arizona. American Atomics
manufactures small tubes containing tritium gas for distribution to other
licensees some of which place the tubes in timepieces for distribution to
other companies for sale. The inspection disclosed an allegation regarding
irregularities in quality control during manufacture or testing of the
tubes. A few tubes were reported by consignees as having lost luminosity
indicating the tritium had leaked out of the tubes.
Action to be Taken by NRC Licensees who Received Tubes Containing Gaseous
Tritium from American Atomics Corporation:
1. Examine a minimum of 100 tubes in stock to determine if complete
luminosity is lost, indicating either loss of tritium or that tritium
may not have been put in the tubes. Report in writing: (a) the total
number of tubes in stock at the time of sampling, (b) the number of
tubes examined, and (c) the number of tubes with apparent loss of
luminosity (i.e., failure).
2. Select a random sample of at least 100 tubes from stock supplies and
soak test the tubes in lots of five for 24 hours in a volume of water
equal to 10 times the volume of the tubes to determine leakage of
tritium. Report in writing: (a) the number of tubes in stock when the
sample was selected, (b) the total number of tubes that were tested,
and (c) the number of five tube lots found to be leaking in excess of
50 nanocuries per 24 hours.
3. For those licensees who also posses an NRC exempt distribution license
for distribution to the public of timepieces containing tritium gas
tubes, report in writing: (a) the number of failure during quality
assurance testing of completed lots of timepieces (e.g., vibration
tests, drop tests, etc.) (b) the lot sizes used for the testing and,
(c) whether the testing was performed by the recipient of this Bulletin
or by American Atomics Corporation. The reports submitted should cover
the first calendar quarter of 1979.
4. Review receiving inspection records for tubes received during the first
calendar quarter of 1979. Report in writing: (a) the total number of
tubes received during the period, and (b) the number of tubes rejected
due to apparent loss of luminosity.
.
Draft IE Bulletin No. 79-22 Page 2 of 2
September 5, 1979
Reports concerning Items 1, 2, 3, and 4 should be submitted to the Director
of the appropriate NRC REgional Office with a copy sent to the NRC Office of
Inspection and Enforcement, Division of Fuel Facilities and Materials Safety
Inspection, Washington, D.C. 20555 within 45 days/
Approved by GAO, B180225 (R0072); clearance expires 7-31-80. Approval was
given under a blanket clearance specifically for generic problems.