ISO 21909 pdf download – Passive personal neutron dosemeters一 Performance and test requirements

ISO 21909 pdf download - Passive personal neutron dosemeters一 Performance and test requirements

ISO 21909 pdf download – Passive personal neutron dosemeters一 Performance and test requirements.
emission 01 h9ht exhibited by certain substances or materials when the substance is heated following its exposure to ionizing radiation or U.V.
NOTE Strictly, the pwoperty ahould be referred to as radEo(herrolumbneecenc. hut the abbreviated form Is usuaSy adequate.
thermoluminescence albedo neutron dosemeter albedo doserneter
passive device, consisting of two or more Th detectors, mounted in a holder (appropriate for the application). Intended to detect incident and albedo neutrons when worn on a persons body for the purpose of assessing the appropriate personal dose equivalent at or near the position where it is placed
thermoluminescent detector
specified quantity of TI material, or such material incorporated with other non.luminescent material into a matrix, being defined by mass, shape or size or the mass of material incorporated in the matrix
thermolumlnescenc dosemeter reader TI reader
instrument used 10 measure the light emitted from the detectors of thermoluminescence dosemeters, consisting essentialy of a heating device, a light measuring device and the associated electronics
zero point
reading of unirradiated liDs expressed in apparent photon dose equivalent
3.7 Terms with respect to superheated emulsion dosemeters (SED)
procedure to render superheated emulsions ready for use
NOTE I Bubble detectors (BD) we typically stord and kept inactive under presaur., wtich ii applied keeping their screw caps on They we activated by removing the screw cap
NOTE 2 Superheated drop detectors (SOD) we typically stored and kept inactive at reduced temperature. They are activated by allowing them to read ambient temperature.
bubble reading
reading of a dosemeter based on superheated emulsions
NOTE In bble detectors (BD). the number of vwible bubbles, that oompclse the measurement, is obtained by optical counting or by use of an automatic electro-optical Instrument. In the supeheated &op detectors, the volume of evolved gas is measured with the help of a calibrated scale
decrease in the number of superheated drops &e to thew transformation into bubbles after being shuckt by neutrons
This International Standerd uses SI units. However the following units of practical importance for time are used wtiere necessary: days (d) and hours (h).
5 General test conditions
5.1 Test conditions
All tests shall be performed under standard test conditions (see Annex A). except where otherwise stated, The actual conditions should be indicated in the test report. They should not undergo Large or rapid changes during a series of measurements
Irradiation of dosemeters shall be performed on a phantom In terms of personal dose equivalent for the energy and angle dependence of response tests For the other tests, dosemeters may be irradiated freein-a.r and reference quantity could be neutron f)uence.
5.2 Reference radiation
The reference radiation fields defined in ISO 8529-1 shall be used. In addition, simulated workplace neutron fields may be used (ISO 12789). For many of the tests. it le sufficient to use only one neutron source (e.g.
or Cf neutron Sources). Information on Irradiation oonditions Is found In Annex 0.
NOTE For TLADs, any neutron source with adequate low-energy neutron intensity, the more moderated the better. can be used foi the tests
5.3 Test requirements
All detectors and dosemeters shall be subjected to the preparation, handling and read-out recommended by the manufacturer. Packaging, handling and processing of the detectors and dosemeters govern theIr performance that is generally assessed under laboratory conditions. As these conditions can never adequately swnulate the conditions actuaRy experienced in practical personal dosln’ietiy, caution is therefore necessary when applying the results of these performance tests in real situations.
6 Performance requirements
The foaowing general requirements apply to the tests for al detectors and doserneters.
a) The tests are performed on a specified number of dosenieters randomly selected from one batch.
b) Type tests are made to assess the basic characteristics of the detectors or dosemeters and are often assured by recogrxzed national laboratories, while quality tests are usually done by dosimetry services that intend to use doserneters for routine neutron personal dosimetry.
c) The performance requirements are listed in Tables 6.1 to 6.5 as type tests (TT) or quality tests (OT).
d) The number of dosemeters used ii each test shall be such to demonstrate that the requirements are met at the 95 % confidence level.
a) The reader used in the evaluation of the detectors and dosen,eters shall be subjected to routine tests to establish consistency of operation.
Information on the characteristics of detectors and dosemeters Is given in Annex E.

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