Survey Meters

Anyone who wishes to be taught how to use a hand-held radiation survey meter should contact EHS.  EHS will be happy to come to your lab at your convenience to demonstrate proper use of the survey meter present in the lab (like the ones pictured below).

Survey Meters

Radiation monitoring instruments are available for all personnel handling radioactive materials.  This instrumentation may be present in the lab (hand-held Geiger-Mueller (GM) detectors, for example), in a common area (liquid scintillation counters, for example), or may have to be borrowed from another lab or from the EHS office.

Three basic checks must be performed prior to each use of a hand-held survey meter (like a GM Detector, a.k.a. a Geiger counter):  Battery check, Integrity Check, and Calibration Check.

Battery check: 

For most meters this is done by pressing a button or turning a knob to "BATT" and then ensuring that the needle in the display points to the "BAT OK" or "BAT TEST" region.  If you are not sure how to verify that your meter's batteries are still good, contact EHS.

Survey Meter Face

When the batteries are low, the meter may still sound like it is operating correctly.  It may still make the same "clicking" noises, at the same rate that you are used to. DO NOT BE FOOLED. It does not measure accurately if the batteries are low. Always check the batteries.

Integrity check: 

Ensure the meter doesn't look broken, including checking the thin window behind the detector screen for cracks.

If the meter seems to give spurious counts depending on the orientation of the probe, it may indicate that the cable is shorting out.   When the thin window is cracked, the meter may still sound like it is operating correctly.  It may still make the same "clicking" noises, at the same rate that you are used to. DO NOT BE FOOLED. It does not measure accurately if the detector window is broken. Always verify the integrity of this window. 

Calibration check: 

Ensure the meter has been calibrated within the last year by looking at the calibration sticker on the meter.

Calibration Sticker

Monitoring equipment and instruments used for laboratory surveys and dose measurements must be calibrated annually and following repairs. EHS tracks the annual calibration dates for all survey meters on campus and will arrange for the annual calibrations to be completed.

Failure of Checks:

If any of the checks fail, for example if the batteries are dead and you do not know how to change them, or if calibration sticker is missing or the meter has not been calibrated in the last year, then you must label the meter with a note saying "Out of Service, Do not use" and the date.  You may also contact EHS for a replacement instrument to use while yours is repaired or calibrated.  A tag like the one bleow or even hand-written note on plain paper is sufficient.

Out of Service Tag

Inform the Environment, Health & Safety Office when the survey meter is taken out of service or returned to service.

If purchasing a new instrument, notify the Environment, Health & Safety Office so that it may be included in the inventory listing of all radiation detection instruments.  

Last modified: Jul 01, 2014
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