This document standardizes the requirements for power conversion devices (PCDs) for the computer and telecommunications industries. The phrase “power conversion devices” refers to ac to dc and dc to dc modules, converters and power supplies. This specification sets the requirements for design; qualification testing; conformance testing and manufacturing quality/reliability processes, but does not include the functional requirements of the specific equipment. PCDs addressed in this document are used in the electronics industry to provide conversion of main power sources, usually ac to lower dc voltages either for direct use of electronic circuits, or as a secondary source for additional dc to dc PCDs to provide several dc voltage levels for various electronic devices in a product. Revision A includes more definitive preconditioning tests for surface mount PCD modules used for category 2 devices (dc to dc converters). Revision A also expands the coverage of moisture sensitivity levels (MSLs) for PCDs and addresses corrosion of PCDs in various commercial, manufacturing and uncontrolled external environments. Finally, revision A significantly increases the coverage of HALT (Highly Accelerated Life Testing) description and application to PCDs.