Towards Dust-tolerant Smoke Detection in Future Space Missions

Smoke detection in any space vehicle or habitat is fundamental for safety and mission assurance. If early warning of a fire scenario fails, the contingency may progress to catastrophic outcomes, including loss of crew, loss of vehicle, and loss of mission. Operational experience with smoke detection in spacecraft is currently limited to low Earth orbit, but space missions to farther destinations have different concepts of operations and more extreme environments that levy additional requirements on the hardware. Smoke detection on missions to the Moon and Mars will be particularly challenging as lunar and Martian dust will inevitably enter vehicles and habitats via human activities, despite the best mitigation techniques. Typical spacecraft cabin dust that is airborne in low Earth orbit has been an ongoing challenge, causing false alarms and requiring operational controls, such as turning off smoke detectors during housekeeping. This practice has been acceptable in low Earth orbit but should not be the norm for dusty destinations. This paper will present background information on smoke detection and airborne particulate matter in spacecraft, limitations of existing technologies, and scenarios for false alarms. Further discussion will look at future mission environments with more stringent requirements, including vehicle autonomy and cabin pressures. A previous paper introduced a smoke detector to prevent false alarms in lunar missions by smoke-dust discrimination (ICES-2020-125), and this paper augments the technology summary with engineering hardware considerations for future missions.