<div class="htmlview paragraph">The object of this paper is to create an awareness of low cycle fatigue problems, the environmental influence of operational differences on parts life, the development of rotating part life limits, life limit increase methods, and the controls required for safe operation.</div> <div class="htmlview paragraph">The major life consumption parameters are defined. Correlation methods of relating actual operating environmental conditions to empirical and test data are presented. Direct measurement of operational differences, variations and configuration differences is made by techniques using an electron microscope.</div>