United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 89-12: Dose Calibrator Quality Control

                                  UNITED STATES
                          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

Addressees:

All NRC medical licensees.

Purpose:

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.









8902060122
.                                                            IN 89-12
                                                            February 9, 1989  
                                                            Page 2 of 3


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. 

Discussion:

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.
.                                                            IN 89-12
                                                            February 9, 1989
                                                            Page 3 of 3


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
                    (301) 492-0571


Attachments:  
1.  List of Recently Issued NMSS Information Notices
2.  List of All Recently Issued NRC Information Notices
.                                                            Attachment 2 
                                                            IN 89-12
                                                            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.
               Cable Sizing

89-10          Undetected Installation       1/27/89        All holders of OLs
               Errors In Main Steam Line                    or CPs for BWRs.
               Pipe Tunnel Differential
               Temperature-Sensing Elements
               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.
               Shutdown Margin

89-08          Pump Damage Caused by         1/26/89        All holders of OLs
               Low-Flow Operation                           or CPs for nuclear
                                                            power reactors.

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
               Generators Inoperable

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 
                                                            torus shells. 

89-05          Use of Deadly Force by        1/19/89        All holders of OLs
               Guards Protecting Nuclear                    for nuclear power
               Power Reactors Against                       reactors.
               Radiological Sabotage
_____________________________________________________________________________
OL = Operating License
CP = Construction Permit 
..
Page Last Reviewed/Updated Tuesday, November 12, 2013