Information Notice No. 89-12: Dose Calibrator Quality Control
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
WASHINGTON, D.C. 20555
February 9, 1989
Information Notice No. 89-12: DOSE CALIBRATOR QUALITY CONTROL
All NRC medical licensees.
This notice is provided to alert recipients to a frequent problem concerning
dose calibrator quality control tests, identified by NRC inspectors during
inspections of medical programs, and also to emphasize the importance of
quality control procedures for equipment used to assay patient doses. It
is expected that licensees will: review this information for applicability
to their programs; distribute this notice to those responsible for radiation
safety and medical quality assurance, including technologists; and consider
actions to preclude similar situations from occurring at their facilities.
However, the suggestions contained in this notice do not constitute any new
NRC requirements, and no written response is required.
Description of Circumstances:
During recent NRC inspections of medical facilities, inspectors have found
deficiencies and irregularities in the performance and recording of dose
calibrator quality control tests. The most common deficiency is a failure
to evaluate the recorded measurements against expected values, in order to
validate proper dose calibrator operation within the tolerances specified
in NRC regulations, licensee operating procedures, and license conditions.
Technologists often base their dose calibrator acceptance criteria solely
on the lack of any sudden or large changes in the recorded measurements,
rather than using the approved, required NRC standards. NRC inspectors
have documented several instances where measured readings have gradually
deviated from expected values; yet, licensees have failed to detect, and
therefore correct or repair, malfunctioning dose calibrators. In some
instances, a dose calibrator was later determined to be functioning properly,
but the test itself had been performed improperly. In all of these instances,
prompt evaluation of recorded results would have assured proper performance
of tests and validation of measured patient doses.
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February 9, 1989
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Other types of problems related to the use of dose calibrators have also been
identified. In some cases, licensees have identified a malfunctioning dose
calibrator, but then failed to take action to correct the problem. In one
particular instance, the licensee's consultant made initial arrangements for
a replacement dose calibrator after a linearity test demonstrated
non-linearity, but the licensee did not act on the consultant's recommendation
and waited one month before retesting the dose calibrator. In other cases,
technologists failed to perform constancy checks when emergencies required the
dose cali-brator to be used during periods such as weekends, when
radiopharmaceuticals are not normally administered to patients.
Of serious concern to the NRC is the finding, during several inspections, that
false information was recorded for dose calibrator tests. In one case, a
consultant requested a technologist to repeat the linearity test. Instead of
repeating the test, the technologist created a record using the results of a
linearity test performed 30 months before the recorded date. In another case,
an NRC inspection at a hospital revealed records indicating that a cobalt-57
check source (half life of 271 days) had not shown any decay in two months,
resulting in a 15% decrepancy.
All medical licensees are reminded of the importance of making accurate
quality control checks of dose calibrators used to assay patient dosages.
NRC believes that the performance and evaluation of these dose calibrator
checks are necessary to ensure that the dosage administered is the same
as the dosage that was prescribed for the patient. These checks are es-
sential steps for assuring safety and quality in the medical use of byproduct
material. Therefore, licensees should assure that technologists or other
individuals performing dose calibrator checks understand:
a) the applicable NRC regulations and specific license conditions;
b) the purpose, method, and importance of these tests; and
c) when follow-up actions are necessary.
Licensees may wish to consider some type of audit or verification program to
detect performance errors, including: failure to perform a test, inadequate
evaluation of a test, or falsification of test records. Audits should include
interviews with and observations of personnel performing their duties, as well
as reviews of records to determine that the recorded results are correct.
Licensees are reminded that they are held responsible for the acts of their
employees and contractors. Willful failure to perform required dose cali-
brator tests and falsification of records have resulted in civil penalties
and orders modifying licenses to prohibit the involvement of individuals
responsible for licensed activities. Willful violations can also result
in criminal prosecution against both the licensee and individual employees.
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February 9, 1989
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No written response is required by this information notice. If you have any
questions about this matter, please contact the appropriate NRC regional
office or this office.
Richard E. Cunningham, Director
Division of Industrial and
Medical Nuclear Safety
Office of Nuclear Material
Safety and Safeguards
Technical Contact: Sam Jones, NMSS
1. List of Recently Issued NMSS Information Notices
2. List of All Recently Issued NRC Information Notices
. Attachment 2
February 9, 1989
Page 1 of 1
LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information Date of
Notice No._____Subject_______________________Issuance_______Issued to________
89-11 Failure of DC Motor-Operated 2/2/89 All holders of OLs
Valves to Develop Rated or CPs for nuclear
Torque Because of Improper power reactors.
89-10 Undetected Installation 1/27/89 All holders of OLs
Errors In Main Steam Line or CPs for BWRs.
Pipe Tunnel Differential
at Boiling Water Reactors.
89-09 Credit for Control Rods 1/26/89 All holders of OLs
Without Scram Capability or CPs for test and
in the Calculation of the research reactors.
89-08 Pump Damage Caused by 1/26/89 All holders of OLs
Low-Flow Operation or CPs for nuclear
89-07 Failures of Small-Diameter 1/25/89 All holders of OLs
Tubing in Control Air, Fuel or CPs for nuclear
Oil, and Lube Oil Systems power reactors.
Which Render Emergency Diesel
89-06 Bent Anchor Bolts in 1/24/89 All holders of OLs
Boiling Water Reactor or CPs for BWRs
Torus Supports with Mark I steel
89-05 Use of Deadly Force by 1/19/89 All holders of OLs
Guards Protecting Nuclear for nuclear power
Power Reactors Against reactors.
OL = Operating License
CP = Construction Permit
Page Last Reviewed/Updated Friday, May 22, 2015