2-10. CONTROL MEASURES
a. Inspection. Frequent inspections are conducted for leaks or tears in the
seals of microwave devices.
(1) Inspection guidelines -- microwave ovens. It is impossible to determine
but there are some visual checks which can be made. Almost all instances of leakages
are around the door area; therefore, these checks can be made:
(a) Loose or bent hinges and screws missing from door hinges.
(b) Sprung, warped, or misaligned doors.
(c) Faculty interlocks; for example, the oven should not be operable
with the door open or slightly ajar.
(d) Worn, missing, or damaged seals around the door or viewing area.
(e) Pitting and burn spots around the periphery of the door closure
area. This is usually caused by arcing as a result of grease buildup around the door.
Check ovens at frequent intervals to eliminate this arcing which causes an increase in
leakage levels.
(f) Reflection from metal objects can increase leakage; therefore,
check to be sure personnel are not using metal or aluminum foil cooking containers.
(g) Be sure ovens are not being operated empty. If you want to
operate the oven without food to check its operation; for example, the door locks, put a
small bowl or beaker of water in the oven.
(h)
Be sure appropriate operating signs are posted.
(2) Survey--detection equipment microwave ovens. Leakage tests. The
Narda 8200 is the approved instrument for making leakage tests. This device will
measure leakage levels from about 0.1 mW/cm2, is battery-operated, easy to use, and
covers the most popular oven frequency of 2450 MHz.
b. Medical Surveillance. Personnel working around microwave devices are
monitored for health problems.
MD0587
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