Answer to Question #8495 Submitted to "Ask the Experts"

Category: Instrumentation and Measurements — Instrument Calibration (IC)

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

Q

I used a particular ionizing radiation survey instrument (Geiger counter) at our facility, until it quit working. So my maintenance department bought me a new one. I'm trying to figure out if this new instrument would be considered an instrument meeting acceptable quality standards. Are there standards or requirements for radiation survey instruments that we should be meeting?
 

For a similar example, in an Occupational Safety and Health Administration regulation, it requires that sound-level measurements are "measured by equipment conforming at least to the Type 2 requirements of American National Standard Specification for Sound Level Meters, S1.4-1971 (R1976), and to the Class II requirements of American National Standard Specification for Octave, Half-Octave, and Third-Octave Band Filter Sets, S1.11-1971 (R1976)."

A

If you are working for a facility, licensed to possess and/or use radioactive materials, under the federal government—e.g., US Nuclear Regulatory Commission (US NRC) or US Department of Energy (DOE)—or under a US NRC Agreement State, then there are certain operational requirements that instruments used in support of your radiation safety program are expected to meet. For example, the US NRC, in 10 CFR 20.1501, requires each licensee to make surveys as necessary to comply with the regulations. Implicit in this requirement are the expectations that the instruments being used are suited for the measurements of interest, which means that the instruments respond properly to the radiations of interest and that they provide readouts that are acceptably accurate for the measurement being made. In 20 CFR 1501(b) the NRC specifies the requirement for calibrating instruments intended for quantitative measurements. 10 CFR 35.60 and 35.61 also state requirements for portable instruments used in medical facilities. Generally, instruments to be used for routine measurements should be calibrated at least annually. The DOE provides for similar requirements in 10 CFR 835.401(b) and provides specific support information in document DOE G 441.1-7.

Most licensing agencies also accept and/or recommend guidance for instrument performance and calibration provided through certain national standards groups and policy-making organizations. These groups and agencies include the American National Standards Institute (ANSI), the Health Physics Society (HPS), and the National Council on Radiation Protection and Measurements (NCRP). Examples of significant documents that specify operational and calibration requirements for health physics measurements are ANSI N323, American National Standard Radiation Protection Instrumentation Test and Calibration (1978); ANSI N323a, Radiation Protection Instrumentation Test and Calibration (1997); ANSI N323b, Installed Radiation Protection Instrumentation Test and Calibration - Portable Survey Instruments for Near Background Operation (2003); ANSI N42.17A, American National Standard for Performance Specifications for Health Physics Instrumentation-Portable Instrumentation for Use in Normal Environmental Conditions (2003); ANSI 42.17c, Performance Specifications for Health Physics Instrumentation-Portable Instrumentation for Use in Extreme Environmental Conditions, American National Standard (1989); and NCRP Report 112, Calibration of Radiation Protection Survey Instruments (1991).

I hope this is helpful to you.

George Chabot, PhD, CHP

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Answer posted on 26 August 2009. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, 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. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.