Jump to content

Studying Combustion and Fire Safety


Recommended Posts

  • Publishers

Research on the International Space Station is helping scientists to understand how fire spreads and behaves in different environments and learn how to prevent and extinguish fires in space. Combustion investigations contribute to the safety of crew members, equipment, and spacecraft by guiding selection of spacecraft cabin materials, improving understanding of fire growth, and identifying optimal fire suppression techniques. This research also contributes to fire safety on Earth and some studies improve our understanding of combustion for uses such as producing electricity and powering vehicles on the ground.

Microgravity dramatically influences flames and provides a unique environment for studying combustion. For example, on Earth, hot gases from a flame rise and gravity pulls cooler, denser air to the bottom of a flame, creating the classic shape and flickering effect. In microgravity, this flow doesn’t occur and on the space station, low-momentum flames tend to be rounded or even spherical. By removing the effects of buoyancy, microgravity provides researchers a better understanding of specific flame behaviors.

Rubins, wearing a grey shirt, black pants, and blue gloves, pulls hardware from a round hatch on the Combustion Integrated Rack. The hardware has a series of silver connectors and orange hoses attached to a black device. The walls of the station around Rubins are covered with equipment, cords, and wires.
NASA astronaut Kate Rubins works on the space station’s Combustion Integrated Rack.

The Combustion Integrated Rack (CIR), developed and operated by NASA’s Glenn Research Center, provides a secure and safe environment for a wide range of combustion experiments. Different chamber inserts that enable a variety of investigations include the Multi-user Droplet Combustion Apparatus, which supported FLame Extinguishment Experiments (FLEX), the Advanced Combustion via Microgravity Experiments (ACME) insert, and the Solid Fuel Ignition and Extinction – Growth and Extinction Limit (SoFIE) chamber.

FLEX, which analyzed the effectiveness of fire suppressants, led to the discovery of a type of cool flame, where the fuel continued “burning” under certain conditions after extinction of the visible flame. Typical flames produce carbon dioxide and water, but cool flames produce carbon monoxide and formaldehyde. Learning more about the behavior of these chemically different flames could lead to the development of more-efficient, less-polluting vehicles. Cool flames produced on Earth quickly flicker out. Since they burn longer in microgravity, scientists have the opportunity to study them.

FLEX-2 looked at how quickly fuel droplets burn, the conditions required for soot to form, and how mixtures of liquid fuels evaporate before burning. Results could help make future spacecraft safer and increase fuel efficiency for engines using liquid fuel on Earth.

ACME is a set of six independent studies using the CIR to examine fuel efficiency and pollutant production in combustion on Earth. The series also looked at improving spacecraft fire prevention through a better understanding of materials flammability.

One ACME investigation, Flame Design, studied the quantity of soot produced under different flame conditions. Soot, the carbon residue left when carbon-containing material does not fully burn, causes environmental and health issues but is desirable for some purposes. Results could enable the design of flames with more or less soot, depending on the specific need, and may help create more efficient and less polluting designs for burning fuel.

ACME’s Burning Rate Emulator (BRE) simulated the flammability of solid and liquid materials by burning gaseous fuels under specific conditions. Analysis of 59 BRE burn tests provided data on heat flow, flame size, effects of fuel mixture flow, and other important parameters.1 Results could improve the fundamental understanding of materials flammability and assess whether existing methods for testing flammability are effective in microgravity.

A nearly spherical flame points sideways, dark blue on its edge becoming bright yellowish orange in its center and darker orange at the end of several tongues of flame extending to the right.
Image of a flame burning one of the BASS tests on extinguishing burning fuels.

Burning and Suppression of Solids (BASS) was one of the first investigations to examine how to extinguish fuels burning in microgravity. Putting out fires in space must consider flame geometry, characteristics of the materials, and methods used to extinguish it, because methods used on the ground could be ineffective or even make the flame worse.

BASS-II examined the characteristics of a variety of fuel samples to see whether materials burn as well in microgravity as in normal gravity, given the right conditions. Several papers have reported results from BASS-II, with findings including the differences between flame spread and fuel regression and comparison of flame spread rates.2,3

Astronaut Samantha Cristoforetti reconfigures combustion research components
ESA (European Space Agency) astronaut Samantha Cristoforetti works on the SoFIE-GEL investigation of materials flammability.

SoFIE-GEL analyzes how the temperature of a fuel affects material flammability. Researchers report that experiment observations agree with trends predicted by the models. This investigation, the first in a series, tested various fuels including flat sheets, thick slabs, cylinders, and spheres.

Saffire is a series of experiments conducted aboard uncrewed Cygnus cargo spacecraft after they depart the station, which makes it possible to test larger fires without putting crew members at risk. Results on flame spread in microgravity can be used to establish the rate of heat release in a spacecraft4 and show that reducing pressure slows down that spread.5

A sample of fabric burns inside Spacecraft Fire Experiment-IV (Saffire-IV). The sample is a composite fabric made of cotton and fiberglass and is 40 cm wide. The image appears green on the right because green LED lights are used to illuminate the sample during the burn. An orange flame sits top to bottom in the center of the image with a dark region between the orange and green areas. Bright specks on a black background to the left of the orange area show the smoldering cotton that remains on the fiberglass substrate after the flame passes
A sample of fabric burns inside an uncrewed Cygnus cargo spacecraft for the Saffire-IV experiment.

Confined Combustion, sponsored by the ISS National Lab, examines flame spread in confined spaces of different shapes. Confinement affects fire characteristics and hazards. Researchers report specifics on interactions between a flame and its surrounding walls and the fate of the flame, such as growth or extinction.6 These results provide guidance for the design of structures, fire safety codes, and response in space and on Earth. Other results suggest that confinement can increase or decrease solid fuel flammability depending on conditions.7

FLARE, an investigation sponsored by JAXA (Japan Aerospace Exploration Agency), also tests the flammability of materials in microgravity. Results could significantly improve fire safety on future missions.

male astronaut setting up hardware for a combustion experiment
JAXA astronaut Satoshi Furukawa sets up hardware for the FLARE investigation.

Flame studies help keep crews in space safe. This research also could lead to more efficient combustion that reduces pollutants and produces more efficient flames for uses on Earth such as heating and transportation.

Search this database of scientific experiments to learn more about those mentioned above.


  1. Dehghani, P., Sunderland, P.B., Quintiere, J.G., deRis. J.L. Burning in microgravity: Experimental results and analysis. Combustion and Flame. Vol 228, June 2021, pp 315-330
  2. Huang X, Link S, Rodriguez A, Thomsen M, Olson SL, Ferkul PV, Fernandez-Pello AC. Transition from opposed flame spread to fuel regression and blow off: Effect of flow, atmosphere, and microgravity. Proceedings of the Combustion Institute. 2019 37(3): 4117-4126. DOI: 10.1016/j.proci.2018.06.022.
  3. Bhattacharjee S, Laue M, Carmignani L, Ferkul PV, Olson SL. Opposed-flow flame spread: A comparison of microgravity and normal gravity experiments to establish the thermal regime. Fire Safety Journal. 2016 January; pp 79111-118. DOI: 10.1016/j.firesaf.2015.11.011
  4. Urban DL, Ferkul PV, Olson SL, Ruff GA, Easton JW, Tien JS, Liao YT, Li C, Fernandez-Pello AC, Torero JL, Legros G, Eigenbrod C, Smirnov N, Fujita O, Rouvreau S, Toth B, Jomaas G. Flame spread: Effects of microgravity and scale. Combustion and Flame. Vol 199 January 2019; pp 199168-182. DOI: 10.1016/j.combustflame.2018.10.012.
  5. Thomsen M, Fernandez-Pello AC, Urban DL, Ruff GA, Olson SL. Upward flame spread over a thin composite fabric: The effect of pressure and microgravity. 48th International Conference on Environmental Systems, Albuquerque, New Mexico. 2018 July 8; p ICES-2018-23111
  6. Li Y, Liao YT, Ferkul PV, Johnston MC, Bunnell CT. Experimental study of concurrent-flow flame spread over thin solids in confined space in microgravity. Combustion and Flame. Vol 227, May 2021; pp 22739-51. DOI: 10.1016/j.combustflame.2020.12.042
  7. Li Y, Liao YT, Ferkul PV, Johnston MC, Bunnell CT. Confined combustion of polymeric solid materials in microgravity. Combustion and Flame. Vik 234 Dec 2021; pp  234111637. DOI: 10.1016/j.combustflame.2021.111637.

View the full article

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Topics

    • By NASA
      5 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Science in Space: June 2024
      The Sun wields a huge influence on Earth. Its gravity holds our planet in its orbit, and solar energy drives the seasons, ocean currents, weather, climate, radiation belts, and auroras on Earth.
      The solar wind, a flow of charged particles from the Sun, constantly bombards Earth’s magnetosphere, a vast magnetic shield around the planet. The Sun occasionally releases massive amounts of energy, creating solar geomagnetic storms that can interfere with communications and navigation and disrupt the electric power grid.
      The colorful aurora borealis or Northern Lights and aurora australis or Southern Lights are created by the transfer of energy from solar electrons to molecules in Earth’s upper atmosphere. Those molecules then release that energy in the form of light. Different molecules create specific colors, such as green from oxygen.
      Because Earth’s magnetic field directs solar electrons toward the poles, auroras typically are visible only at high latitudes, such as in Canada in the north and Australia in the south. But solar storms can send the lights into much lower latitudes. During a series of large solar eruptions in May 2024, for example, the display could be seen as far south as Texas and California.
      Satellites captured auroras visible across the globe on May 11, 2024.NOAA NASA has multiple missions studying how the Sun and solar storms affect Earth and space travel. The International Space Station contributes to this research in several ways. 
      Improved Solar Energy Measurements
      The station’s Total and Spectral Solar Irradiance Sensor (TSIS) measures solar irradiance, the solar energy Earth receives, and solar spectral irradiance, a measure of the Sun’s energy in individual wavelengths. Knowing the magnitude and variability of solar irradiance improves understanding of Earth’s climate, atmosphere, and oceans and enables more accurate predictions of space weather. Better predictions could in turn help protect humans and satellites in space and electric power transmission and radio communications on the ground. 
      The first five years of TSIS observations demonstrated improved long-term spectral readings and lower uncertainties than measurements from a previous NASA mission, the Solar Radiation and Climate satellite. The accuracy of TSIS observations could improve models of solar irradiance variability and contribute to a long-term record of solar irradiance data. 
      Earlier Sun Monitoring
      Installation of the Solar instruments on the space station during a spacewalk.NASA The ESA (European Space Agency) Sun Monitoring on the External Payload Facility of Columbus, or Solar, collected data on solar energy output for more than a decade with three instruments covering most wavelengths of the electromagnetic spectrum. Different wavelengths emitted by the Sun are absorbed by and influence Earth’s atmosphere and contribute to our climate and weather. This monitoring helps scientists see how solar irradiance affects Earth and provides data to create models for predicting its influence. 
      One instrument, the Solar Variable and Irradiance Monitor, covered the near-ultraviolet, visible, and thermal parts of the spectrum and helped improve the accuracy of these measurements.  
      The SOLar SPECtral Irradiance Measurement instrument covered higher ranges of the solar spectrum. Its observations highlighted significant differences from previous solar reference spectra and models. Researchers also reported that repeated observations made it possible to determine a reference spectrum for the first year of the SOLAR mission, which corresponded to a solar minimum prior to Solar Cycle 24. 
      Solar activity rises and falls over roughly 11-year cycles. The current Solar Cycle 25 began in December 2019, and scientists predicted a peak in solar activity between January and October of 2024, which included the May storms. 
      The third instrument, SOLar Auto-Calibrating EUV/UV Spectrometers, measured the part of the solar spectrum between extreme ultraviolet and ultraviolet. Most of this highly energetic radiation is absorbed by the upper atmosphere, making it impossible to measure from the ground. Results suggested that these instruments could overcome the problem of degrading sensitivity seen with other solar measuring devices and provide more efficient data collection. 
      Auroras from Space
      An aurora borealis display photographed from the International Space Station.NASA Astronauts occasionally photograph the aurora borealis from the space station and post these images.  
      For the CSA (Canadian Space Agency) AuroraMAX project, crew members photographed the aurora borealis over Yellowknife, Canada, between fall 2011 and late spring 2012. The space images, coordinated with a network of ground-based observatories across Canada, contributed to an interactive display at an art and science festival to inspire public interest in how solar activity affects Earth. The project also provides a live feed of the aurora borealis online every September through April.  
      Student Satellites
      Deployment of the Miniature X-ray Solar Spectrometer and other CubeSats from the space station.NASA The Miniature X-ray Solar Spectrometer CubeSat measured variation in solar X-ray activity to help scientists understand how it affects Earth’s upper atmosphere. Solar X-ray activity is enhanced during solar flares. Students at the University of Colorado Laboratory for Atmospheric Space Physics built the satellite, which deployed from the space station in early 2016. 
      Better data help scientists understand how solar events affect satellites, crewed missions, and infrastructure in space and on the ground. Ongoing efforts to measure how Earth’s atmosphere responds to solar storms are an important part of NASA’s plans for Artemis missions to the Moon and for later missions to Mars. 

      Melissa Gaskill 
      International Space Station Research Communications Team 
      NASA’s Johnson Space Center 

      Search this database of scientific experiments to learn more about those mentioned above. 
      Keep Exploring Discover Related Topics
      Latest News from Space Station Research
      Overview The Sun’s gravity holds the solar system together, keeping everything – from the biggest planets to the smallest particles…
      NASA Heliophysics
      Overview The Science Mission Directorate Heliophysics Division studies the nature of the Sun, and how it influences the very nature…
      Station Science 101: Earth and Space Science

      View the full article
    • By NASA
      Credits: NASA NASA has selected KBR Wyle Services LLC, of Fulton, Maryland, to provide safety and mission assurance services to the agency.
      The Safety and Mission Assurance, Audits, Assessments, and Analysis (SA3) Services contract is a cost-plus-fixed-fee contract with an indefinite-delivery/indefinite-quantity provision and a maximum potential value of approximately $75.3 million. The three-year base performance period of this contract begins August 1, 2024, and is followed by a two-year option, which would end July 31, 2029.
      The SA3 contract will provide safety and mission assurance services to NASA Headquarters in Washington and other NASA centers, programs, projects, and activities through the NASA Safety Center in Cleveland. These services include, but aren’t limited to, audit/assessment/analysis support, safety assessments and hazard analysis, reliability and maintainability analysis, risk analysis and management, supply chain data management and analytics, software safety and assurance, training and outreach, quality engineering and assurance, and information systems support.
      For information about NASA and other agency programs, visit:
      Tiernan Doyle
      Headquarters, Washington
      Jan Wittry
      Glenn Research Center, Cleveland
      Last Updated Jun 10, 2024 LocationNASA Headquarters Related Terms
      NASA Centers & Facilities NASA Headquarters NASA Safety Center View the full article
    • By NASA
      2 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Food for the Apollo astronauts was not always especially appealing, but thanks to the protocol NASA and Pillsbury came up with, known as the Hazard Analysis and Critical Control Point (HAACP) system, it was always safe.Credit: NASA Countless NASA technologies turn up in our everyday lives, but one of the space agency’s most important contributions to modern society isn’t a technology at all – it’s the methodology that ensures the safety of the food we eat. Today the safety procedures and regulations for most of the food produced around the world are based on a system NASA created to guarantee safe food for Apollo astronauts journeying to the Moon. 

      For the Gemini missions, NASA and partner Pillsbury tested the food they were producing at the Manned Spacecraft Center, now Johnson Space Center in Houston, and destroyed entire batches when irregularities were found, a process similar to industry practices of the day. In response to agencywide guidelines from the Apollo Program Office aimed at ensuring the reliability of all critical systems, they altered that method for the Apollo missions. 

      They focused on identifying any points in the production process where hazards could be introduced, establishing procedures to eliminate or control each of those hazards, and then monitoring each of those points regularly. And they required extensive documentation of all this work. This became the foundation for the Hazard Analysis and Critical Control Point (HACCP) system. 
      The Apollo missions were humans’ longest and farthest voyages in space, so food for the astronauts had to be guaranteed safe for consumption hundreds of thousands of miles from any medical facility. Credit: NASA
      Howard Bauman, the microbiologist leading Pillsbury’s Apollo work, convinced his company to adopt the approach, and he became the leading advocate for its adoption across the food industry. That gradual process took decades, starting with the regulation of certain canned foods in the 1970s and culminating in the 2011 Food Safety Modernization Act, which mandated HACCP-like requirements across all food producers regulated by the U.S. Food and Drug Administration. By then, the U.S. Department of Agriculture was managing HACCP requirements for meat and poultry, while Canada and much of Europe had also put similar rules in place. 

      The standards also apply to any outside producers who want to export food into a country that requires HACCP, effectively spreading them across the globe.
      Read More Share
      Last Updated Jun 10, 2024 Related Terms
      Spinoffs Technology Transfer Technology Transfer & Spinoffs Explore More
      2 min read New Energy Source Powers Subsea Robots Indefinitely
      Power modules driven by ocean temperatures save money, reduce pollution
      Article 6 days ago 2 min read Tech Today: Measuring the Buzz, Hum, and Rattle
      NASA-supported wireless microphone array quickly, cheaply, and accurately maps noise from aircraft, animals, and more.
      Article 2 weeks ago 2 min read Tech Today: From Spacesuits to Racing Suits
      Article 3 weeks ago Keep Exploring Discover Related Topics
      Technology Transfer & Spinoffs
      Humans in Space
      The Apollo Program
      View the full article
    • By NASA
      “I went back to school in 2016. So I had two kids that were three and five, and I was working full time, and I was doing the master’s program, taking two classes online. It took two years to get it done, and it was like a balancing act, and my kids had to watch the sacrifice in a sense. There were times when I had to take tests, and I was like, ‘OK, you’ve got to sit in the living room with your dad, or you’ve got to go to grandma’s house because I’ve got to take this test.’
      “It was tough, but I had to get it done to show my kids that anything is possible. Things don’t get handed to you. You’ve got to work for them.
      “And so, I made sure that when I graduated in August of 2018, we drove to the school, which is six hours away, so they could watch me walk across the stage and see, you know, the sacrifices I made so that we could be here. And so for them, it’s like – my little one, that’s what she wants to grow up to do: work for NASA and do safety like me. It’s cool.
      “To them, I think it’s impactful, so they know that if you commit yourself and put the effort and work into it, you can do whatever you put your mind to. Both of my kids watched it, and they’re both in the STEM program at their school because they have a passion for math and science and want to try to make a difference in their own capacity.”
      – Thu Nguyen, Facility Systems Safety Engineer and Fall Protection Program Administrator, NASA’s Johnson Space Center
      Image Credit: NASA/Robert Markowitz
      Interviewer: NASA/Tahira Allen
      Check out some of our other Faces of NASA. 
      View the full article
    • By NASA
      NASA has selected Science Applications International Corporation of Reston, Virginia, for safety and mission assurance support at the agency’s Johnson Space Center in Houston, and White Sands Test Facility in New Mexico.
      The Safety and Mission Assurance Engineering Contract III (SMAEC) is an indefinite-delivery/indefinite-quantity contract with the ability to issue cost-plus-award-fee and fixed price task orders. The contract begins June 1 with a five-year base period, followed by two one-year options, with possible extensions of services through November 2031. The total maximum value of the contract is approximately $494 million.
      The contract will provide safety, reliability, and quality engineering, as well as quality and software assurance support for NASA programs and projects in deep space including the Orion spacecraft, Gateway lunar space station, and Extravehicular Activity and Human Surface Mobility, as well as the Commercial Crew, Commercial Low Earth Orbit Development, International Space Station, and Human Research Programs.
      Services also may be provided at other NASA centers, U.S. government facilities, contractor or subcontractor locations, or vendor facilities as provided in the statement of work, or as specified in the issued task orders.
      For information about NASA and agency programs, visit:
      Abbey Donaldson
      Headquarters, Washington
      Kelly Humphries
      Johnson Space Center, Houston
      Last Updated Mar 29, 2024 LocationNASA Headquarters View the full article
  • Check out these Videos

  • Create New...