Fluke Biomedical 37-040 - Manual (Page 7)

Introduction
Storage of Unexposed Dosimeters/Dosimetry Media
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1.5.4 Ultraviolet Light
The dosimetry media have increasing sensitivity to radiation at decreasing wavelengths below the visible
region. Therefore, exposure to any source containing an ultraviolet component, including sunlight, is not
recommended.
1.5.5 Microwave Radiation
Exposure to microwave radiation may cause heating of the dosimetry media and is therefore not
recommended.
1.5.6 Solvents
The vapors of organic solvents may diffuse into the active layer of the dosimetry media and have adverse
effects upon the radiation sensitive component. Incidental contact with such vapors is unlikely to cause
harm, but continuous exposure is to be avoided. Neither is it recommended that any liquid solvent,
aqueous or nonaqueous, be allowed to contact the surface of the dosimetry media. If an aqueous or non-
aqueous solvent were to wet the surface of unexposed dosimeters or media, it is recommended that the
contaminated dosimeters or media be discarded.
1.6 Storage Of Exposed Dosimeters/Dosimetry Media
1.6.1 Temperature
The normally blue color of exposed dosimetry media rapidly converts to an orange-red color at
temperatures above 65°C (149°F). Therefore, never subject exposed dosimeters/dosimetry media to
temperatures exceeding 60°C (140°F). For optimum results store exposed
dosimetry media in the dark,
where the temperature will be below 25°C (77°F).
1.6.2 Relative Humidity
Although high relative humid ity, i.e. <80%, is not deleterious at low temperatures, i.e. <25°C (77°F),
the combination of high temperature, i.e. <60°C (140°F), and high relative humidity can increase the rate
at which the blue to red-orange color change occurs.
Therefore, do not subject exposed dosimetry media to high humidity and high temperature, i.e. <85% RH
and <60°C (140°F). Where possible, it is recommended that exposed dosimeters/dosimetry media be
stored in the dark where the relative humidity is less than 50% and the temperature is below 25°C (77°F).
1.6.3 Visible Light
Although the dosimeters/dosimetry media have almost insignificant sensitivity towards visible light, it is
recommended that unnecessary exposure be avoided, so that the maximum lifetime may be obtained.
This is particularly so because visible radiation sources frequently have an ultraviolet component that will
cause more rapid increases in optical density. Therefore, when exposed dosimeters/dosimetry media are
not being used, do not leave them laying on a laboratory bench or table, the measurement stage of a
densitometer, the sample holder of a spectrophotometer, desktop, etc. Store exposed dosimetry media in
the dark. Exposed dosimetry media should be stored in a glassine, plastic or paper envelope, preferably
black.