1 This guide defines possible sources of uncertainty in dosimetry performed in gamma, X-ray (bremsstrah)ung), and electron irradiation facilities and offers procedures for estimat-ing the resulting magnitude of the uncertainties in the mea-surement of absorbed dose using a dosimetry system. Basic concepts of measurement, estimate of the measured value of a quantity, "true value", error, and uncertainty are defined and discussed. Components of uncertainty are discussed and meth-ods are given for evaluating and estimating their values. How these contribute to the standard uncertainty in the reported values of absorbed dose are considered and methods are given for calculating the combined standard uncertainty and an estimate of expanded (overall) uncertainty. The methodology for evaluating components of uncertainty follows ISO proce-dures (see 2.3). The traditional concepts of precision and bias are not used in this document. Examples are given in five annexes.
2 This guide assumes a working knowledge of statistics. Several statistical texts are included in the references (1-4).
3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.
note: 2 The boldface numbers in parentheses refer to the bibliography at the end of this guide.