Have you ever wondered how fire shelters work?  Here is a basic overview of the design of a fire shelter and how it protects.

The Supply Cache Blogger |

A mandatory piece of protective equipment since 1977, a fire shelter is a portable, one-person tent.  It protects the user primarily by reflecting radiant heat while trapping breathable air.  Fire Shelters are issued to most federal, state, and local wildland firefighting agencies in the United States.  It offers protection from both radiant and convective heat.  When deployed as a last resort, when conditions and time make survival truly impossible, a fire shelter is said to provide the user a 50% chance of survival. This being said, fire shelters have saved the lives of more than 300 firefighters and prevented hundreds from suffering serious injuries.

Today’s fire shelters are comprised of two layers.  The outer layer consists of aluminum foil bonded to woven silica.  The outer layer’s foil will reflect radiant heat while the silica material will slow the passage of heat to the inside of the shelter.  This outer layer will reflect approximately 95% of the radiant heat that touches it.  As a result the temperature of the materials rise slowly due to only 5% of the heat being absorbed into the shelter materials.

A layer of aluminum foil laminated to fiberglass makes up the inner layer.  This prevents heat from reradiating to the person inside the shelter. Further insulation is obtained from the air gap between the layers once the two layers are sewn together.

To conclude we will once again state that a fire shelter should only be deployed if all safety zones and escape routes are no longer an option; a last resort if entrapment is eminent.  Per the The New Generation Fire Shelter (NFES 2710), a NWCG publication by the NWCG Fire Equipment Working Team, March 2003, in cooperation with the USDA Forest Service Technology and Development Center, Missoula, MT… “Take your training seriously. Practice deploying your shelter until deployment is, in the words of one entrapment survivor, “like tying your shoe.” Think of training as life insurance—insurance that if the unthinkable ever occurs, you will have every possible chance to survive.

Credits and for further exploration…

Nix, Steve. "The Fire Shelter." ThoughtCo, Feb. 11, 2020, thoughtco.com/the-fire-shelter-1342906

Joshua Fody and Tony Petrilli. "Developing a more effective fire shelter." NASA, June 15, 2016, https://www.nasa.gov/feature/developing-a-more-effective-fire-shelter

TEXFIRE. "Difference between convective, radiant and by contact heat."  TEXFIRE, Dec. 13, 2017, https://texfire.net/en/blog/55_difference-between-convective-radiant-and-by-contact-heat.html

Leslie Anderson, Project Leader. "The New Generation Fire Shelter." . NWCG Fire Equipment Working Team, March 2013, https://www.fs.fed.us/t-d/pubs/pdfpubs/pdf03512803/pdf03512803dpi300.pdf

 Additional Information

NWCG. “6 Minutes for Safety, Fire Shelter Deployment.” National Wildfire Coordinating Group, Page Last Modified/Reviewed: Oct. 2019, https://www.nwcg.gov/committee/6mfs/fire-shelter-deployment

Mockenhaupt, Brian. “What It Feels Like To Lie Face Down and Let a Wildfire Burn Over You.” The Atlantic,  May 23, 2014, https://www.theatlantic.com/technology/archive/2014/05/fire-shelters/371421/

Keller, Paul. “Your Fire Shelter: Would You Hesitate Deploying It?” Wildland Fire Lessons Learned Center, Fall 2011, Vol. 1 Issue 3, https://www.wildfirelessons.net/HigherLogic/System/DownloadDocumentFile.ashx?DocumentFileKey=fb7177ad-be60-4e97-832b-e407fa8fa0d9&forceDialog=0

Anchor Industries Inc.  (Fire Shelter manufacturer’s website offers PDFs of Fire Shelter Use Instructions in both English and Spanish.)