Fighting fires is one of the world’s most dangerous jobs; and when a fire sparks in the unruly brush and tangled flora of the rural wilderness, the stress of the job can be heightened. Because wildfires can spread quickly and be difficult to control, they pose some of the greatest dangers to the firefighters who bravely attempt to extinguish them.
Enter the fire shelter: a device that firefighters carry with them, allowing them to take cover from the flames and toxic air if they become trapped in a wildfire. Fire shelters have been in use for about 50 years, but the design of this device is constantly being improved. Finding new, safer ways to protect firefighters has long been a priority of the industry, and one that has seen a lot of development in recent years.
According to NASA engineers, progress is being made in their attempts to help the U.S. Forest Service design a better fire shelter to protect wildland firefighters. These efforts are under way in full effect as a result of the deadly Yarnell Hill fire that trapped nineteen firefighters in 2013. In a mission to prevent similar tragedies from occurring in the future, the NASA CHIEFS project, or Convective Heating Improvement for Emergency Fire Shelters, is aimed to help save firefighters’ lives.
It’s a lofty goal, but one that has plenty of innovation and fire safety technology behind it. Take a look at the where firefighter safety shelters started — and where they are headed in the next few years.
A Look Back on Fire Shelter Safety
Invented in the late 1950s, the fire shelter has vastly evolved over the last several decades. The first experimental fire shelters were used for protection from a 1964 fire in California and saved the lives of 36 firefighters. Mass production of fire shelters began in 1967 so firefighters could carry them when necessary. At that time, the fire shelter was made of aluminum foil and fiberglass fabric with a paper liner, in an A-frame configuration.
1960s - 2000s: The Fire Shelter Proves its Worth
The paper liner was removed from the fire shelter design in the 1970s, and seven years later it was mandated that all U.S. federal firefighters must carry fire shelters. Slight changes were made over the years to continue improving the design; and from the 1960s to the 2000s, fire shelters saved around 300 firefighters and prevented serious burns to another 300. The safety device, while strong, was not invincible. During the same time period, 20 firefighters lost their lives in fire shelters — reiterating the importance of protection from the devastating effects of fire.
2000 - 2002: A New Generation of Safety
Forest Service Fire Management officials decided it was time to pursue the development of a more effective fire shelter in 2000. Under what is now named Missoula Technology and Development Center, or MTDC, various materials and designs were created and tested. The New Generation Fire Shelter was selected in 2002, showing noticeable improvement in fire protection over its predecessors. It still is unable to offer adequate protection in the worst fire conditions, though.
2014: Continuing the Pursuit of Ultimate Fire Protection
The Fire Shelter Project Review was launched in 2014 to pursue advanced materials that might offer greater protection by reducing the speed of heat transfer through the layers of the shelter. Many heat-resistive materials of the past were toxic, heavy, fragile, and/or bulky — making them inappropriate for shelters.
The Future of Fire Shelters
The CHIEFS effort by NASA is aimed to improve the fire shelter’s resistance to flame exposure. Researchers have developed an apparatus to test exposure to extreme heat which uses a propane flame on numerous material samples. This apparatus has been used to evaluate the thermal performance of hundreds of material layups.
After passing the first screening, the materials deemed promising are made into full-scale shelters for continued testing. In 2015, researchers assessed the initial round of CHIEFS full-scale shelters and shelters submitted by others in controlled wildfires and laboratory fire tests.
The CHIEFS team is currently completing production of another round of fire shelters to be tested. All of the shelters will endure first round evaluations and the best candidates will face evaluation in a second round of testing. The goal for the CHIEFS team is to create a fire shelter with enhanced performance — and very little increase in weight and bulk — that can face testing in the field, to keep our nation’s wildland firefighters as safe as possible while on the job.