Most Probable Fire Scenarios in Spacecraft and Extraterrestrial Habitats: Why NASA's Current Test 1 Might Not Always be Conservative

). Its simple pass-fail criteria eliminates materials that burn for more than 12 inches from a standardized ignition source. In addition, if a material drips burning pieces that ignite a flammable fabric below, it fails. The applicability of Test 1 to fires in microgravity and extraterrestrial environments, however, is uncertain because the relationship between this buoyancy-dominated test and actual extraterrestrial fire hazards is not understood. There is compelling evidence that the Test 1 may not be the worst case for spacecraft fires, and we don’t have enough information to assess if it is adequate at Lunar or Martian gravity levels.