scope:

This is a guideline technical report that gives formulae to estimate the reliability of fibre under a constant service stress. It is based on a power law for crack growth which is derived empirically, but there are other laws which have a more physical basis (for example, the exponential law). All these laws generally fit short-term experimental data well but lead to different long-term predictors. The power law has been selected as a most reasonable representation of fatique behaviour, by the experts of several standard-formulating bodies.