ISO 21909:2021

Description

This document provides methodology and criteria to qualify the dosimetry system at workplaces where it is used. The criteria in this document apply to dosimetry systems which do not meet the criteria with regard 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 in the dose determination for a certain workplace field;

-    or, that the correction factor or function used for this specific studied workplace enables the dosimetry system to accurately determine the conventional dose value with uncertainties similar to the ones given in ISO 21909-1.

NOTE       This document is directed at all stakeholders who are involved: IMSs, accreditation or regulatory bodies, and users of the particular dosimetry (the user is meant as the entity which assigns the dosimetry system to the radiation worker and records the assigned dose.)

The methodologies to characterize the work place field in order to perform the qualification of the dosimetry system are given in Annex A. Annex B is complementary as it gives the practical methods to follow, once one methodology is chosen.

The provider of the dosimetry system shall provide the type test results corresponding to ISO 21909‑1. However, when the dosimetry system to be qualified does not comply with all the criteria of ISO 21909‑1 dealing with the energy and angle dependence of the response, some tests of the ISO 21909-1 can be not performed.

The links between ISO 21909-1 and ISO 21909-2 are described in Annex E.

This document only addresses neutron personal monitoring and not criticality accident conditions.