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addition to reading the information presented here, Drawell recommends that
instrument users participate in a radiation safety and operational training class offered
by Drawell.
WARNING: treat radiation with respect. Do not hold your analyzer
near the window during testing. Never point your
analyzer at yourself or anyone else when the shutter is
open.
4.1 Radiation Protection Basics
The TrueX analyzer contains an x-ray tube which emits radiation only when the
user turns the x-ray tube on. When the x-ray tube is on and the shutter is open, as
during a measurement, the analyzer emits a directed radiation beam. Reasonable
effort should be made to maintain exposures to radiation as far below dose limits as is
practical. This is known as the ALARA (As Low as Reasonably Achievable) principle.
For any given source of radiation, three factors will help minimize your radiation
exposure: Time, Distance, and Shielding.
4.1.1 Time
The longer you are exposed to a source of radiation, the longer the radiation is
able to interact in your body and the greater the dose you receive. Dose increases in
direct proportion to length of exposure.
4.1.2 Distance
The closer you are to a source of radiation, the more radiation strikes you. Based
on geometry alone, dose increases and decreases with an inverse-squared relation to
your distance from the source of radiation (additional dose rate reduction comes from
air attenuation). For example, the radiation dose one foot from a source is nine times
greater than the dose three feet from the source. Remember to keep your hands and all
body parts away from the front end of the analyzer when the shutter is open to
minimize your exposure.
4.1.3 Shielding
Shielding is any material that is placed between you and the radiation source. The
more material between you and the source, or the denser the material, the less you
will be exposed to that radiation. Supplied or optional test stands are an additional
source of shielding for analysis. A backscatter shield accessory is also available and
may be appropriate in some applications.
