In the days following 9/11 Bruce Colborne joined millions of horrified television viewers who watched as emergency workers laboring in the smoke, dust and fumes at Ground Zero.
"Like everybody else, I watched the 9/11 coverage from my living room without being able to actually do anything about it," Colborne said. "I remember feeling guilty as I watched all of the emergency workers in that environment without a clean, comfortable place to recover."
As an independent air conditioning contractor, Colborne had a thought. Why not build something that would be portable enough that they could pull it right onto the site and provide a cool environment to rest?
That idea developed into Texas-based Rapid Air Shelter, manufacturer of inflatable climate controlled shelters designed to protect emergency responders from weather and other harsh environments. Available in modular unit sizes ranging from 120 to 320 square feet, the Rapid Air Shelter is a fully integrated system -- shelter, generator and trailer, plus other important extras to aid at the emergency scene.
Before the first shelter was built Colborne spent six months interviewing firefighters to learn what they needed most from such a unit.
"They came up with a pretty impressive list," Colborne said. "It had to be portable, self-deploying, provide hot and cold conditioned air, positive pressure, with carbon dioxide detection, stay in place and also a smoke removal system. It needed to be compact and match their fire truck colors."
As a rule, modern firefighters require at least 10 minutes rest or "rehab" after 45 minutes of strenuous activity or using two 30-minute SCBA bottles. That rehab should occur away from whatever hostile environment confronts the firefighters. But the big rehab trailers designed for large scale emergencies are rarely rolled out for small scale events that fill the day for most firefighters.
"Unfortunately, today's firefighters usually end up lying in the parking lot and spraying water on each other," Colborne said. "If it's 100 degrees or more outside it's hard to recover that way. Effective fire fighter rehab is very important. One of the biggest problems for the fire department is fire fighters succumbing to heart attacks or heat exhaustion."
After the interviews came a year of design work, Colborne said. The smallest size shelter built by Rapid Air Shelters measures 10 feet by 12 feet and fits into a short bed pick up truck or a small trailer. Beside emergencies, the shelter can also be used as a refuge during public events such as football games. The largest individual shelter size is 16 feet by 20 feet and fits into a 12-foot trailer. The customers looking for larger shelters have been taking advantage of the modularity of the RAS systems and combining a number of smaller shelters into a single larger complex. All the shelters have removable end panels for a zipper connection to shelters of the same size. Including the portable generator, air conditioning unit, and shelter the trailer has a gross vehicle weight rating of 4,000 pounds. It can easily be towed behind a half-ton pickup truck or sports utility vehicle. Future designs include incorporating an RAS package in the side storage cabinets of fire trucks.
As the airframe is inflated the shelter unfurls much like a sleeping bag. Total deployment takes less than 15 minutes, Colborne said.
"Once inflated it stays in place," Colborne said. "There are no guide wires or stakes to hold it to the ground. Firefighters asked for a shelter that could withstand a 35 mph wind without moving." Anchoring the Rapid Air Shelter are large water-filled tubes serving as ballast that run the length of the shelter. Water is carried with the trailer, fed into the shelter by a hose.
Once inflated it remains upright without a continuous air supply.
"A lot of these type of shelter are require constant air flow, meaning that if the unit loses electrical power it collapses," he said.
The Rapid Air Shelter itself is made from panels of nylon fabric impregnated with rubber for lightweight durability. Each panel is fireproof and safe to a temperature of 150 degrees F. By removing zippered end walls, multiple shelters can be joined together to create a larger structure if needed. Also, zippered panels make repairs and maintenance a simple matter.
Everything needed to support the shelter comes with the trailer. Most important of which is the high efficiency air conditioning and heating unit.
"The front door is built out of warehouse strips," Colborne said. "Firefighters can hit it at a full run, go through it, land on the floor, strip off that 80 pounds of equipment and lay right in the air conditioning."
Air conditioning provides another important advantage to the Rapid Air Shelter. The shelter can be kept at a positive pressure that keeps smoke and any other contaminants out.
"We've got a hospital system looking at Rapid Air Shelter as a triage area outside their emergency room," Colborne said. "Hospitals don't want to contaminate their interior working space. Within minutes they could set up a shelter and have all personnel arrive through the RAS before entering the hospital. Positive pressure means the rest of the hospital can be protected."
Cooled or heated air pumped into the tent is also kept clean by the Rapid Air Shelter utilizes an electronic filter that uses activated charcoal to remove smoke, bacteria, odors, allergens, mold, volatile organic contaminants and some toxic gases, Colborne said.
"The filter uses the same media that were used to clean up the post offices in Washington, D.C., and New Jersey affected by the 2001 anthrax attack."
For further protection, RAS includes a carbon dioxide monitoring system.
"It's wired directly to a switch that immediately shuts off the unit," Colborne said. "That way if the monitor does go off someone has to stop and figure out what shut the unit off. It can't prevent 100% of carbon dioxide poisonings but it can alert the occupant to a potential problem."
Inflation, temperature control, filtration and a system of built-in lights are powered by a diesel generator that is located in the trailer. The generator is sized to meet Rapid Air Shelter air conditioning load plus 15 percent more.
"The trailer is designed so that everything is modular," Colborne said. "Take the generator, for instance. If the generator fails all the connections to it are soft connections." This means that the generator can quickly be removed and replaced with a new unit. Also, all controls for the RAS are monitored from one central control panel to make the unit as user friendly as possible.
Each fire department has different on board equipment storage requirements. Rapid Air Shelter meets these requirements by providing ample storage space complete with and industrial, sound attenuated cabinet and lockable access doors. Beyond that, each shelter is custom-built to the specifications of the individual departments, right down to the color of the shelter and the addition of department logos.
Federal grant money is available and can be used to make the purchase, making them affordable to smaller departments, Colborne said. The Texas Engineering Extension Service conducted testing that led to approval by the federal Office of Emergency Preparedness. Some customers are in the approval process for grant money from the Department of Homeland Security.
"RAS offers the luxury of having everything integrated into one unit," he said. "In the past the customer needed to deploy a a setup crew the day before, then bring in a generator and find the technical people required to safely wire it up. We're actually building a small shelter that deploys from the pack of a pickup truck or trailer." o