R&M 2000 Environmental Stress Screening

Abstract

Air Force policy requires the implementation of Environmental Stress Screening (ESS) programs on electronic equipment procurements and the establishment of ESS for electronic inventory repair. The purpose of this policy is to move failures, due to weak parts and poor workmanship, out of the field and back into the factory. This procedure will improve field reliability and, thereby, increase combat capability. When properly applied, ESS quickly precipitates latent defects to failure without damaging equipment. Air Force ESS policy requires that electronic equipment manufacturing and repair processes begin with high-quality piece parts as measured by a defective rate of 100 parts/million or less. The policy calls for a minimum of thermal and random vibration screening during various stages of the manufacturing process according to a baseline ESS regimen. Alternative regimens are permissible provided they are as effective as the baseline regimen in reducing premature failures in the field. This paper discusses ESS theory as it relates to Air Force policy and also outlines a graphical technique for illustrating the effectiveness of ESS regimens based on field experience.