30 | PRM-7000 / 8000 / 9000 Users Guide
3. If a suspected object, or part of an object is detected, locate the meter
in close proximity and take a timed-measurement to determine the spe-
cifi c measurement and the extent to which the measurement exceeds
the normal background count of the area.
4. If while performing guideline 1 above, no obvious increases are no-
ticed, this does not mean that the object is completely free of radiation.
Users should take timed measurement(s) of suspected objects and
compare the result with the normal background radiation.
14.4 Scanning for Surface Contamination
To check for radioactive contamination of a surface, please us the following guidelines:
1. Using two coins of equal size, or other shims, orient the PRM Instru-
ment vertical with the sensor window pointed towards the surface.
2. Use a timed measurement or simply reset the counters of the PRM
Instrument and allow the device to measure overnight.
NOTE: Do not allow a surface that may be contaminated to come in direct contact
with the PRM Instrument. Use spacers or shims to isolate the PRM Instrument from
the surface and if any contamination is found, dispose of the spacers appropriately.
14.5 Measuring Food
Measuring food for radiation typically requires advanced equipment and procedures.
Because many foods are largely composed of water (itself a radiation shield), thorough
detection often requires a special oven for “ashing” the foods. Ashing removes the water
and concentrates any radioactivity present. Measuring radiation in food is also complicat-
ed by the fact that many foods, such as dried bananas and Brazil nuts, contain naturally
occurring radiation. Individuals have several options for determining whether the food
that they consume contains radiation:
• Make no assumption and take no action and be 100% blind to the presence of
radiation in food.
• Assume that the food has been scanned to the standards set forth by various gov-
ernment agencies and departments and is safe for consumption.
• Purchase and use the same advanced equipment and related procedures that such
agencies use to conduct their tests
• Use a personal radiation monitor such as a PRM Instrument that may not be as
sensitive, accurate and thorough as advanced methods but does provides users
with some level of assurance.
To Next Page
Loading...
Need help?
General