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National Aeronautics and Space Administration

EVA 23 Suit Water Intrusion

with water possibly saved his life. The flight control team quickly discussed and sorted through multiple possible explanations for the water in the helmet. The ISS Program has assembled an investigation team which has responded to this failure with a level of concern and has applied resources that demonstrate its awareness of both the seriousness of this event and the importance of fully understanding and correcting the deficiencies that allowed it to happen. Many of the recommendations in this report have already been implemented or are under discussion as a result of the involved organizations’ proactive response. All voting members of the board participated in the investigation, deliberations, and development of the findings and recommendations. Upon completion of the deliberations, all voting members were polled and were in agreement with the findings and recommendations as written. There were no dissenting opinions, and therefore a minority report section is not included in the report. Summary of Findings The appointment letter instructed the MIB to place the highest priority on determining corrective actions necessary to prevent similar mishaps from occurring. Using the process described above, the MIB conducted a Root Cause Analysis (RCA). Timelines and an Event and Causal Factor Tree (ECFT) were developed, leading to the identification of one primary undesired outcome (PUO) that revealed three proximate causes, 19 intermediate causes, 30 observations, 13 contributing factors, and 49 recommendations. Five root causes were identified for the mishap at the organizational level under the PUO. Primary Undesired Outcome: ECFT UO 1 - EVA crew member (EV2) exposed to potential loss of life during EVA 23 The primary undesired outcome of this mishap was that the EV crewmember experienced a large amount of water collecting inside his helmet which created several hazardous conditions including risk of asphyxiation, impaired vision, and a compromised ability to communicate. Secondary Undesired Outcome: The Crew and ISS were exposed to a potential fire hazard due to inadvertent activation of the EMU 3011 Secondary Oxygen Pack during EMU dryout activities. During the course of this investigation, the MIB identified an additional undesired outcome addressed here as Secondary Undesired Outcome (SUO). Section 2.5 discusses the events involving the SUO. No additional causes, findings, or observations were generated solely as a result of this SUO. Rather, the causes, findings, and recommendations that centered on the PUO address the issues identified that caused the SUO.


ISS EVA Suit Water Intrusion Mishap Investigation Report  

Report of the NASA Mishap Investigation Board examining the high visibility close call event of July 16, 2013 when ESA astronaut Luca Parmit...