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Model : Reading Dosimeter
Hãng sản xuất : RPD
The Direct Reading Dosimeter is a pocket-size, carbon fiber electroscope with an ion chamber for detecting and indication of integrated exposure to gamma and x-ray radiation. It has a thin wall which permits the penetration and detection of radiation. A yearly calibration of the Direct Reading Dosimeter is recommended, and is generally consistent with good health physics practices. More frequent calibration may be necessary should the user’s license require a shorter calibration interval.
The way to read a dosimeter is to point it at a light source so that you can look through it and see the scale. The conductive fiber moves across a very clear, well-marked scale that produces the reading. Because the dosimeter scale is linear, it is possible to determine the total amount of radiation exposure for any selected period of time by merely subtracting the reading taken at the end of the selected period. It is not necessary to recharge the dosimeter after each reading unless the instrument reads close to full scale.
These dosimeters use an extremely sensitive fiber electrometer type voltmeter and a small volume of air to measure the total amount of radiation to which the instrument has been exposed. A reading may be made at any time by looking at the light source through the eyepiece end of the instrument.
Dosimeters are extremely sensitive instruments. Although they are constructed for rugged use and have a protective sapphire window, they should receive the same care as a wristwatch. Since dosimeters are hermetically sealed at the factory, they cannot be repaired or adjusted in the field. Therefore, if the instrument malfunctions in any way it should be returned to the dealer.
Dosimeters may be maintained in operating condition simply by cleaning the eye piece lens and the charging switch insulator with water and a lint-free cloth that is free of grit.
Do not use any alcohol-based products to clean the dosimeter. Make sure the charging switch insulator is free of lint and moisture at all times.
Caution: Do not insert any sharp objects into the charging switch recess or tamper with its parts in any way.
Specifications
Radiation Detected: Gamma and X-ray from 16 keV to 2 MeV
Ranges: 0-200 mR to 0-500 R
Detector: Fiber electrometer mounted in an electrically conductive plastic ion chamber
Detector Housing: Very low permeability plastics - hermetically sealed
Accuracy: Within ± 10% of true exposure
Rate Response: Dose rate independent for gamma and X-ray
Electrical Leakage: Less than 1% of full scale for 24 hours at 50°C
Temperature Range: -20°C to + 50°C
Relative Humidity: Up to 90%
Dimensions: 0.6" Dia. x 4.5" (1.5 x 12.4 cm)
Weight: 1.0 oz (28.4 g)
Finish: Barrel and end caps are natural matte black with metal clips
Shelf Life: 20 years
Warranty: 2 year limited warranty
Specifications: ANSI N13.5 and ANSI N322-1997
1.22" H (55 x 31 mm)
Weight: 1.5 lb (0.7 kg)