At Illinois Home Day in June, local fire chiefs invited congressional staffers to participate in a hands-on exercise at a suburban training center. Outfitted in complete turnout gear with SCBA, small groups entered the smoke-filled burn tower for a few minutes. While inside, each had the opportunity to use a thermal-imaging camera.

The legislative aides recognized the importance of TICs in firefighting, based on comments they made as they exited the structure. Seeing was believing.

Military Origins

Like many other pieces of fire service equipment, thermal imagers trace their beginnings to the military.

English Electric Valve (EEV) developed thermal imagers for the British Navy, which used them in shipboard fighting in the fifties and sixties. Thermal imagers were created for visibility at night and eventually smoke-covered battlegrounds. The first units were considered secured, sensitive military technology, large both in size and cost.

Jack McLoughlin, president of Fire Research Corp., first encountered the thermal imagers when he worked as an engineer for Grumman in the sixties. The imagers were quite reliable and used on aircraft during the VietNam War.

In the early seventies, McLoughlin imported the first thermal imagers from EEV for use by fire departments. Unfortunately, McLoughlin discovered that the heat from fires would cause a white-out on the screen with the early models of TICs.

In the late seventies, larger companies like Texas Instruments, Honeywell and Raytheon began developing several different types technologies for thermal-imaging devices. With financial support from the federal government, thermal-imaging technology evolved, decreasing in price and size. The first thermal imagers for the fire service ranged from $18,000 to $25,000. Demand for thermal imagers during the 1991 Gulf War drove production volumes up and costs came down.

According to Bullard, thermal imaging is based on the theory that all objects have temperature and emit waves of energy called infrared radiation. These energy waves are translated into a viewable picture with hot objects shown as white and cooler objects as black, with gray shades in between. Recent versions of thermal-imaging cameras offer color images.

TICs are used primarily in firefighting to determine the location of the fire and hot spots during overhaul; locating victims; and during ventilation and many other rescue and special operations. According to an article in MSA's 2004 Thermal Imaging magazine, most fire departments underuse their TICs because of they don't understand the full potential of the equipment. MSA recommends educational programs that combine theory and practical training. Programs should “reinforce the features and characteristics of the department's specific camera, combining that knowledge with image interpretation and tactical applications gained in the classroom, followed by hands-on, live fire scenarios.”

Late this summer, the report on comments to NFPA 1801, Thermal Imagers for the Fire Service, will be available at www.nfpa.org for public viewing for seven weeks. According to Bruce Teele, NFPA staff liaison, the standard's technical committee received 265 public proposals last year, most involving Section 8.12 on testing TICs.

“The section was completely revised based on the public comments,” Teele said. “The [report] should be on the NFPA Web site by Aug. 28.” The revised edition will go into effect next year.

Today, thermal-imaging cameras are found across the globe, and across myriad industries. While law enforcement and security, aviation, industrial and commercial businesses have benefited from this technology, the fire and emergency services are still exploring new ways to use TICs to save lives — including their own.

Related Stories

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• Infrared in the aftermath
• Image Conscious

How a TIC Works

In some respects, the detector in the thermal-imaging camera is similar to the human eye. The thermal imager's detector (called a focal plane array, or FPA) and the eye are both receivers. They receive electromagnetic energy and convert it into an image for our brains to interpret. The eye receives wavelengths of energy called “visible light,” while the FPA receives wavelengths of heat energy called “infrared radiation.”

The human eye and the TIC do not “see” through most materials. Drywall, plaster, concrete, steel, wood, paneling, down comforters, doors, sofas and the like are not transparent to visible light or infrared radiation. They “see” only what is on the surface: colors for the eye, temperature differences for the TI. However, due to the unique characteristics of IR, the user can see through thick smoke.

Text provided by Bullard