NASA and other government and industry partners have made substantial progress this year in the development of technical standards that effectively mitigate the longstanding and growing threat posed by electrostatic discharge (ESD). NASA has adhered to industry standard ANSI/ESD S20.20 since the late ‘90s, and is now working with the ESD Association (ESDA) to incorporate NASA’s quality requirements in a Space Addendum to the standard.

The addendum will bridge the gap that formed between Aerospace and the Defense (A&D) organizations as a result of the generalized, versus technically detailed, requirements contained in S20.20 and the latitude it gives for substantial tailoring.

ESD, the sudden transfer of a static electric charge through an electronic component, can potentially degrade a part, rendering it inoperable or installing a latent defect that can manifest itself after the part has been placed in-service. Latent defects are particularly problematic as they cannot be screened out using nondestructive testing, can be significant cost and schedule risk drivers, and can cause full or partial mission failure. Stricter quality controls will help mitigate these risks.

The Need for an Addendum — A Brief History

NASA first recognized the severe risk that ESD posed to electronic parts and assemblies in the 1970s. By the mid-1990s, NASA had written several “best practice” documents on how to avoid ESD damage, and in 1995, NASA formally documented mandatory requirements to control and mitigate ESD risks in Workmanship Standard NASA-STD-8739.7.

However, a few years later, NASA cancelled this standard in order to comply with OMB Circular A-119, which directs federal agencies to adopt industry standards. At that time, the most respected industry organization researching and writing standards for ESD control was the ESDA, and NASA centers and contractors were directed to use S20.20.

Unfortunately, the cancelation of the NASA standard resulted in unforeseen risks and increased, rather than decreased, the threat of ESD damage to flight hardware. The generalized requirements lacked the strict ESD quality requirements of the NASA standard and led to the A&D community becoming widely divergent in many areas of ESD control, with many organizations forgoing proven ESD avoidance practices altogether.

NASA recognized this shortcoming and the need to maintain uniformity within itself and its industrial base, and engaged the ESDA in an effort to incorporate its previously existing quality requirements into their technical standard. This effort, which has been ongoing for several years, is now coming to fruition with the addition of the Space Addendum.

Creating the Space Addendum

Initially, the ESDA had some objections to the addendum that were rooted in a lack of understanding of the high-reliability needs of the space industry. However, after numerous discussions with NASA and like-minded A&D organizations, the ESDA has agreed that adding a Space Addendum to the S20.20 baseline standard solves the A&D community’s need for rigorous quality and environmental controls, while also providing heightened confidence that organizations are fully compliant with these requirements.

The Space Addendum will be written as a Technical Report (TR). TRs are particularly advantageous to A&D stakeholders in that they can be directly invoked in NASA contracts with flow-down to subcontractors. The TR is being drafted by the ESDA A&D committee, which is on track to complete it by the end of calendar year 2014. Gene Monroe, NASA Langley Research Center, currently is serving as committee chair in support of OSMA’s Workmanship Program and Program Manager Jeanette Plante.

Questions related to this article or NASA Workmanship Program efforts to mitigate ESD risk may be directed to Monroe.