Fire safety in spacecraft: Past incidents and Deep Space challenges

Fire safety is listed among the areas of prime concern for inhabited space exploration. The naturally high risk of an accidental fire has to be carefully assessed to avoid damaging consequences to both the crew and the spacecraft while fulfilling the objectives of the mission. Twelve acknowledged incidents from past exploration programs are compiled and contrasted here. The causes and consequences are described within their respective technological contexts, to show how fire safety planning has evolved and learnt from those incidents. In the process, missing information and knowledge gaps are brought forward to avoid any misinterpretation of the facts and evaluate the adequacy of the updated fire strategies. Eventually, the present fire provisions in the International Space Station are analysed to understand how a safe and sustainable situation is achieved in Low Earth Orbit. Yet, with long-range long-duration missions planned in the near future, there is a need to rethink existing solutions. New issues specific to Deep Space exploration are detailed, to understand the nature of emerging threats and identify paths of future research.