BS ISO 6980-3:2006

This part of ISO6980 describes procedures for calibrating and determining the response of dosemeters and doserate meters in terms of the International Commission on Radiation Units and Measurements (ICRU) operational quantities for radiation protection purposes. However, as noted in ICRU Report 56, the ambient dose equivalent, H*(10), used for area monitoring of strongly penetrating radiation, is not an appropriate quantity for any beta radiation, even that which penetrates 10mm of tissue (Emax>2 MeV). For beta particles, the calibration and the determination of the response of dosemeters and doserate meters is essentially a three-step process. First, the basic field quantity, absorbed dose to tissue at a depth of 0,07mm in a tissue-equivalent slab geometry is measured at the point of test, using methods described in ISO6980-2. Then, the appropriate operational quantity is derived by the application of a conversion coefficient that relates the quantity measured (reference absorbed dose) to the selected operational quantity for the selected irradiation geometry. Finally, the reference point of the device under test is placed at the point of test for the calibration and determination of the response of the dosemeter. Depending on the type of dosemeter under test, the irradiation is either carried out on a phantom or free-in-air for personal and area dosemeters respectively. For individual and area monitoring, this part of ISO6980 describes the methods and the conversion coefficients to be used for the determination of the response of dosemeters and doserate meters in terms of the ICRU operational quantities directional dose equivalent, and personal dose equivalent, Hp(0,07). This part of ISO6980 is a guide for those who calibrate protection-level dosemeters and doserate meters with beta-reference radiation and determine their response as a function of beta-particle energy and angle of incidence. Such measurements can represent part of a type test during the course of which the effect of other influence quantities on the response is examined. This part of ISO6980 does not cover the in situ calibration of fixed, installed area dosemeters. The term “dosemeter” is used as a generic term denoting any dose or doserate meter for individual or area monitoring. In addition to the description of calibration procedures, this part of ISO6980 includes recommendations for appropriate phantoms and the way to determine appropriate conversion coefficients. Guidance is provided on the statement of measurement uncertainties and the preparation of calibration records and certificates.