Gap DCS3: We do not know the mission related factors that contribute to DCS risk.
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
Description

Initial  State:

The characteristics of the ISS EVA environment are well understood, but this is not the case with new DRMs. For instance, it is known that activity level during depressurization has a significant effect on the development of DCS. At any given depressurization, an increase in activity level increases the DCS risk. In addition, certain movements tend to be more provocative than others, possibly due to the forces generated by movement in different joints. NASA is going to locations where there is either no or little human EVA experience. Many factors contribute to DCS risk and all of these factors need to be understood in order to provide updates to models and/or to the development of environmental and EVA simulations for PB validation trials.

Interim stages:

#

Task Title

Step Title

Targeted Data

Step Weight

Status: 0=incomplete 1=complete

1

EVA and Environmental Characterization

Environmental Characterization – define and understand the effect of environmental factors on DCS risk

Cabin pressure profiles

5%

0

Cabin breathing gas concentration profiles

5%

0

EVA Characterization - define and understand the effect of EVA factors on DCS risk

Suit pressure profiles

5%

0

Suit breathing gas concentration profiles

5%

0

Prebreathe times

5%

0

Metabolic profiles

5%

0

GRF profiles

5%

0

EVA duration

5%

0

Mission Factors - define and understand the effect of environmental factors on DCS risk

EVA frequency

5%

0

EVA quantity

5%

0

Crew size

5%

0

2

EVA Simulator

NEA EVA Simulator

EVA simulation to be used during PB validation trials

15%

0

Lunar EVA Simulator

EVA simulation to be used during PB validation trials

15%

0

Mars EVA Simulator

EVA simulation to be used during PB validation trials

15%

0

Gap Closure:

0%


Approach:

These tasks will aim to mine for factors and data relevant to DCS risk with respect to each DRM as aspects of these factors might change based on the definition. Much of these data will be provided by other groups and some such as the characterization of metabolic rates and force profiles for proposed EVA tasks in proposed EVA environments is research that will need to be done. These tasks and the associated physiological characteristics will then be used to update the DCS risk model, provide inputs to the DCS risk vs. WEI analysis and to create an EVA simulation to be used with PB validation studies.

Target for Closure
EVA simulator for use in PB validation trials. Inputs to the definition of acceptable risk (Gap 1). Obtain effect size as a function of individual variance for each risk factor of interest in order to include in the DCS prediction model.
Mappings
Risk Risk of Decompression Sickness [inactive]
You are here! Gap DCS3: We do not know the mission related factors that contribute to DCS risk.
Completed

Multi-Disciplinary Research Plans

Documentation:
No Documentation Available