Cost effectiveness of environmental stress screening (ESS): a case history

Environmental stress screening (ESS) seems like an expensive process, but it actually saves money in the long run. Performing a low budget ESS program on 20 newly manufactured circuit cards presented an ideal opportunity to prove that ESS is an engineering tool that management should promote. The screen precipitated defects that could have occurred on the aircraft, thus, improving the reliability of the system. When the economics of the project were examined, a greater return on investment (ROI) than anticipated was realized. This successful ESS project initiated support for an intensive ESS program. An ESS program incorporates trained personnel, adequate time, cooperation, environmental chambers, fixtures, power suppliers, interconnects, monitoring equipment, a reliable failure analysis program, etc. However, if limitations exist in any of the above items, an adequate ESS program can still be successfully performed yielding improvements in reliability