Fire safety and compartmentation

Key results

• Fire is the most likely serious hazard.
• It is more likely than a large air loss lamontagne, 2022-10-07. Paul451 ranks fire as the #1 risk and proximity operations/docking as the #1 danger Paul451, 2019-03-31.
• lamontagne's building-code process lists fire as likely and depressurization as rare lamontagne, 2024-02-28.
• Compartmentation.
• Subdivide into airtight sections sized by Earth egress codes: ~50 m to a safe spot, ~60 sections for a big ring lamontagne, 2022-10-07.
• IBC chapter 10 egress, sprinklers, areas of refuge, submarine bulkhead practice JohnFornaro, 2022-10-07.
• Twark_Main's cellular structure: size modules so occupants can evacuate into neighbours at the maximum leak rate Twark_Main, 2023-09-25; Twark_Main, 2023-09-26.
• Two independent pressure sections act as each other's lifeboat lamontagne, 2023-04-18; lamontagne, 2026-09-16.
• Heat release data (lamontagne): garbage fire 500 kW for 5 min; subway car 15 MW for up to 30 min; car 6–10 MW; fuel truck 200 MW. Smoke fans are rated 2 h at 200 °C lamontagne, 2022-10-09; lamontagne, 2022-10-09; lamontagne, 2022-10-09.
• Suppression options:
• Nitrogen flooding (Inergen) is effective but costly lamontagne, 2022-10-09.
• Halon production halted in 1994 Eric Hedman, 2022-10-09.
• Water mist; vent until the fire is out, then flood with nitrogen Paul451, 2022-10-09.
• Seal and vent to space Surfdaddy, 2022-10-08.
• Intake (partial vacuum) and outtake (pressurized) tanks create airflow and ingest smoke; ban paper Coastal Ron, 2022-10-08; Coastal Ron, 2022-10-09.
• Combine the ballast water with the fire-sprinkler reserve; NFPA allows combined systems lamontagne, 2023-11-06.
• Pressure. Fires raise pressure, so relief valves are needed; "paint, plastic, cotton, food, lubricants, aluminium, people burn" Barley, 2022-10-09; Barley, 2022-10-09.
• Passive over-pressure venting to space as a failsafe Paul451, 2022-10-09. Overpressure vents should be small, spring-closed and alarmed Paul451, 2022-10-24.
• Doors. A double hatch between modules acts as a pseudo-airlock and allows late evacuation. "Never design doors that trap people" Paul451, 2022-10-10. ISS bulkhead hatches are manual Paul451, 2018-08-06.
• Materials. Nomex and polyethylene everywhere, though flammable mikelepage, 2022-10-21. JohnFornaro's "organic" natural materials JohnFornaro, 2022-10-10.
• Forest fires on a ring station JohnFornaro, 2024-03-12.

Open questions

• Is gas flooding or venting to vacuum the preferred suppression method for large occupied volumes?
• Do Earth building codes (egress distance, compartment size) transfer directly to rotating habitats?

Related pages

• Emergency and lifeboats · Life support · Module sizing

Sources

Forum posts

• Paul451, 2018-08-06 (reply #1185, 1 like): ISS hatches manual. Post.
• Paul451, 2019-03-31 (reply #1460): Fire #1 risk; docking #1 danger. Post.
• lamontagne, 2022-10-07 (reply #1919): Fire more likely than air loss. Post.
• JohnFornaro, 2022-10-07 (reply #1922): IBC ch. 10; areas of refuge. Post.
• Surfdaddy, 2022-10-08 (reply #1936): Seal & vent. Post.
• Coastal Ron, 2022-10-08 (reply #1937): Intake/outtake tanks. Post.
• Barley, 2022-10-09 (reply #1939, 1 like): Fires raise pressure. Post.
• Paul451, 2022-10-09 (reply #1940, 1 like): Passive over-pressure vent. Post.
• Eric Hedman, 2022-10-09 (reply #1942): Halon. Post.
• Coastal Ron, 2022-10-09 (reply #1943): Nitrogen flooding. Post.
• Paul451, 2022-10-09 (reply #1944, 2 likes): Water mist, vent, N₂. Post.
• Barley, 2022-10-09 (reply #1952, 3 likes): What burns. Post.
• lamontagne, 2022-10-09 (reply #1954, 2 likes): Heat release rates. Post.
• lamontagne, 2022-10-09 (reply #1955, 2 likes): Smoke fans. Post.
• lamontagne, 2022-10-09 (reply #1956, 3 likes): Suppression options. Post.
• Paul451, 2022-10-10 (reply #1957): Never trap people. Post.
• JohnFornaro, 2022-10-10 (reply #1959): Organic station. Post.
• mikelepage, 2022-10-21 (reply #2171): Flammable materials. Post.
• Paul451, 2022-10-24 (reply #2201, 1 like): Inward hatches held shut. Post.
• lamontagne, 2023-04-18 (reply #3615): Mutual refuge sections. Post.
• Twark_Main, 2023-09-25 (reply #4022, 1 like): Cellular structure (1 like). Post.
• Twark_Main, 2023-09-26 (reply #4026): Evacuation-sized modules. Post.
• lamontagne, 2023-11-06 (reply #4286): Ballast + sprinkler reserve. Post.
• lamontagne, 2024-02-28 (reply #4501, 2 likes): Building-code safety process (2 likes). Post.
• JohnFornaro, 2024-03-12 (reply #4547): Forest fires. Post.
• lamontagne, 2026-09-16 (reply #5114): Two independent sections. Post. Attachments: Kalpana 2b-full.jpg, Kalpana 2b.jpg, Image20_003.jpg.

External references

• International Building Code (IBC), chapter 10 (Means of egress).
• NFPA combined sprinkler/storage provisions.