DIN 25456-1:1999-10

The document constitutes the basis of parts two to six. It deals with the use of the Gaussian method determining the uncertainty of the fast neutronfluence measured in nuclear reactors by activation or fission detectors. Sources of uncertainties (variances and covariances) and mathematical models for input and output quantities are described. The document includes a description of the causes likely to require corrections and uncertainties of measurements, as well as the requirement for a detailed documentation of used facts andmethods of measurements.