ISO 21909-2-2021 pdf free download – Passive neutron dosimetry systems — Part 2: Methodology and criteria for the qualification of personal dosimetry systems in workplaces
This document provides methodology and criteria to qualify the dosimetry system at workplaces whereit is used.The criteria in this document apply to dosimetry systems which do not meet the criteria withregard to energy and direction dependent responses described in ISO 21909-1.
The qualification of the dosimetry system at workplace aims to demonstrate that:
– either, the non-conformity of the dosimetry system to some of the requirements on the energy or
direction dependent responses defined in ISO 21909-1 does not lead to significant discrepancies inthe dose determination for a certain workplace field;
or, that the correction factor or function used for this specific studied workplace enables thedosimetry system to accurately determine the conventional dose value with uncertainties similarto the ones given in ISO 21909-1.
NOTE This document is directed at all stakeholders who are involved:IMSs, accreditation or regulatorybodies, and users of the particular dosimetry (the user is meant as the entity which assigns the dosimetry systemto the radiation worker and records the assigned dose.)
The methodologies to characterize the work place field in order to perform the qualification of thedosimetry system are given in Annex A.Annex B is complementary as it gives the practical methods tofollow, once one methodology is chosen.
The provider of the dosimetry system shall provide the type test results corresponding to lS0 21909-1.However, when the dosimetrysystem to be qualified does not comply with all the criteria of lSO 21909-1dealing with the energy and angle dependence of the response, some tests of the ISO 21909-1 can be notperformed.
The links between lSO 21909-1 and lS0 21909-2 are described in Annex E.
This document only addresses neutron personal monitoring and not criticality accident conditions.
2Normative references
The following documents are referred to in the text in such a way that some or all of their contentconstitute requirements of this document. For dated references,only the edition cited applies. Forundated references, the latest edition of the referenced document (including any amendments) applies.ISO 21909-1:2021, Passive neutron dosimetry systems — Part 1: Performance and test requirements forpersonal dosimetry
ISO8529-2:2000, Reference neutron radiations — Part 2: Calibration fundamentals of radiation protectiondevices related to the basic quantities characterizing the radiation field
ISO 8529-3:1998,Reference neutron radiations —Part 3: Calibration of area and personal dosimeters anddetermination of response as a function of energy and angle of incidence
3.3Calibration and evaluation3.3.1
conventional true value for the neutron personal dose equivalentHconv
quantity value attributed by agreement to a quantity for a given purpose
Note 1 to entry:The conventional value Hnv is the best estimate of the quantity to be measured, determined by aprimary standard or a secondary or working measurement standard which are traceable to a primary standard.Note 2 to entry: in this document, the quantity is the neutron personal dose equivalent.
[SOURCE:ISO/IEC Guide 99:2007,2.12, modified — the term was changed.]3.3.2
calibration
operation that, under specified conditions, in a first step, establishes a relation between the quantityvalues with measurement uncertainties provided by measurement standards and correspondingreadings with associated measurement uncertainties and, in a second step, uses this information toestablish a relation for obtaining a measurement result from an indication
Note 1 to entry: Calibration may be expressed by a statement,calibration function,calibration diagram,calibration curve, or calibration table. In some cases, it may consist of an additive or multiplicative correction ofthe indication with associated measurement uncertainty.
Note 2 to entry: Calibration should not be confused with adjustment of a measuring system, often mistakenlycalled “self-calibration”, or with verification of calibration.
Note 3 to entry: Often, the first step alone in the above definition is perceived as being calibration.ISO 21909-2 pdf download