Human Systems Integration Division @ NASA Ames

This document assesses non-auditory effects of noise relevant to habitable volume requirements in cislunar space. Challenges to NASA's future manned journeys to cislunar space and Mars are described within the Human Exploration and Operations Exploration Objectives document (NASA, 2016). Phase I of the exploration objectives call for a four-person crew to assemble and eventually occupy a module, the 'Orbital ATK cislunar habitat,' by ~2020 as part of the Deep Space Gateway (DSG) in NASA mission EM-31. The objective of Phase II reflects the buildup and shakedown of the Deep Space Transport (DST) vehicle that must also support a four-person crew, up through NASA mission EM-9, by 2028–9. The DSG habitat is planned to evolve over time to a much larger research platform—by ~2024 to include a pair of modules having many of the capabilities required for supporting a human mission to Mars (Gebhardt, 2016; Cichan et al., 2017). Four astronauts are scheduled to occupy a pressurized volume of ~300 m3 for ~30–60 days during Phase I in DSG, and for up to 400 days during Phase II in DST2.

The general health impacts of long-term habitation on humans within such confined environments have been well documented and researched by NASA (e.g., Connors et al., 1985). In space flight and habitats, the auditory effects of noise can be significant due to long-term exposure and momentary higher levels during launch, abort, and descent. The auditory effects of noise are understood primarily via analysis of crew dosimetry and acoustic measurements from within the International Space Station (ISS) and other space habitats, resulting in robust hearing conservation programs and standards that directly address noise levels known to impact health (Limardo et al., 2017).

Less understood are the non-auditory effects of noise pertinent to sleep quality, psychological wellbeing, cognitive performance, and team dynamics. Although auditory effects of noise are known to be highly significant, NASA needs to understand which non-auditory effects of noise are significant to mission success, which non-auditory effects have impact on crew performance, the cost-benefit of mitigation strategies, and possible needs for more detailed measurement techniques or additional standards to address significant impacts.