Gap DCS5: We do not know what validated procedures will adequately prevent DCS.
Last Published:  07/30/21 01:05:31 PM (Central)
Responsible Element: Human Health Countermeasures (HHC)
Status: Closed
Closure Rationale

While DCS research and operational development is of high importance, this work is now funded by organizations other than HRP, in a collaborative joint effort. Details of DCS-related work that is already being done (or planned to be done) may be found in the comprehensive NASA technical paper “Integrated Extravehicular Activity Human Research and Testing Plan” (NASA/TP-2019-220232). As part of HRP’s new strategy, it will contribute to these operational efforts as needed.

Closure Documentation:
No Closure Documentation Available

Initial state:
Validated procedures to prevent DCS exist for the ISS, but not for the Exploration Program. Current DCS prediction models do not extrapolate to the expected Exploration environment and can only be used to help come up with the Exploration atmosphere and PB procedures that needed to be tested on the ground.

Interim stages

Information Needed



PB Accept/Reject Limits Defined



Exploration Atmosphere PB Validation - ground based chamber study



Exploration Atmosphere PB Verification - inflight demonstration study



Gap Closure

0% Complete

Preventing DCS is always preferable to treating DCS. The definition of acceptable risk will help develop Accept/Reject limits for Exploration Prebreathe Protocol Validations. Information from DCS models will be used to determine the Exploration atmosphere and PB procedures. These will be validated using the EVA simulator on the ground and then eventually via spaceflight EVA.

Target for Closure
PB procedures that meet the accept criteria for DCS prevention, which will be based on the definition of acceptable risk standard for the Exploration environment.
Risk Risk of Decompression Sickness [inactive]
You are here! Gap DCS5: We do not know what validated procedures will adequately prevent DCS.

Multi-Disciplinary Research Plans

No Documentation Available