Answer to Question #306 Submitted to "Ask the Experts"

Category: Policy, Guidelines, and Regulations

The following question was answered by an expert in the appropriate field:

When source-checking portable survey instruments prior to use, is it acceptable to perform a source check at the end of shift if the instruments will not be used until the start of the next shift and that shift starts within 24 hours of the source check? If that second shift is such that continuous instrument use extends past 24 hours from the source check, is it unnecessary to perform an additional check?

It sounds like you are looking for an interpretation of ANSI N323-1978,
which states, "A performance check shall be made prior to each use,
during intermittent use conditions, and several times a day during
continuous use." The good news is that the above standard has been
replaced by ANSI-N323A-1997, "Radiation Protection Instrumentation Test
and Calibration," which is less rigorous in the area of concern. The
new standard labels the old performance test as a source response check
and states, ". . . each instrument . . . shall be checked with a source
during operation at least daily, or prior to each intermittent use,
whichever is less frequent." For auditors, the main issue will likely
be whether the radiation protection group of interest meets its own
procedure requirements, rather than the exact definition of a day or
shift. The reader should also be aware that calibration quality
standards are higher in the new ANSI standard. Many labs do not come
close to meeting the standard. The definition of a proper calibration
will likely keep auditors busy for the next few years. For more
information on ANSI Standards go to the American Nuclear Standards Web site.

Roger Schanzenbach, CHP

San Onofre Nuclear Station

The information and material posted on this Web site is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Web site. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.