by Del Williams
Hazmat disposal, medical calls, auto extraction and other emergencies not withstanding, nothing tests a firefighter like fire rescue in a smoke-filled building. The obstacles are many: an unknown floor plan; constriction of sight, sound and breathing; or a rapidly closing window of opportunity to find trapped or unconscious residents in a smoke filled room. Add unexpected equipment failure to the scenario and the result could be a cascading series of events ending in disaster.
One critical tool used by first responders remains quite vulnerable: the flashlight. A broken flashlight lamp when dropped off a landing or down a flight of stairs, dim light due to weak batteries, or a light that simply fails to penetrate the smoke can throw a fire rescue dangerously off track. Fortunately, a brand new light emission method called recoil light-emitting-diode (LED) technology is now being applied in a new generation of flashlights to make fire service jobs both safer and easier.
"Whatever the conditions, we have to enter flammable environments and quickly locate potential burn victims," said Capt. John Garcia of the Houston Fire Department Rescue Unit 11D. "For these situations, task lighting has to work flawlessly and cut through smoke, steam, or whatever stands between us and someone in need of help. There's no room for flashlight failure."
"Typical flashlights reflect off smoke particles with a semi-blinding glare that can make fire suppression or search and rescue difficult," says Lt. George Jones, a rescue tech on fire suppression Truck 18 with the Baltimore City Fire Department. "As batteries weaken and the light dims, their penetration through smoke gets even worse. Thermal imaging devices can help, of course, but they're too expensive and bulky for widespread use. It's more practical for each of us to have an effective, smoke-penetrating flashlight at the ready."
Uses for LED Technology
Recoil light-emitting-diode (LED) technology, in fact, will soon be used in everything from street, traffic and stadium lights to projection TVs and virtually all fixed and portable lighting systems. Although its possible uses appear unlimited, its first practical application is in flashlights that burn 50 percent longer than traditional incandescent bulbs, maintain brightness for up to 10,000 hours of bulb life, and even operate under rugged or underwater conditions.
Derived from the mechanics of lighthouses and locomotive headlights, which demand focused light beams capable of cutting through fog and haze for long distances, recoil LED technology enables better flashlight focus, brightness, longevity, durability and reliability for safer, more effective fire service as well as search and rescue operations.
Torrance, Cal.-based Pelican Products is one of the companies pioneering the new technology for fire and rescue personnel. The company is known for introducing a number of previous lighting innovations including bright-burning Xenon gas bulbs, an anti-shock battery protection system, and third-party safety certification for hazardous environments.
Flashlights with recoil LED technology promise to deliver many benefits for fire and rescue personnel: firemen will be able to see farther and more clearly in smoke-filled or dimly lit situations; hazmat specialists will be able to more clearly assess and dispose of materials in smoky, vaporous or dusty environments; and fire inspectors will be able to more easily survey structures for fire code violations – from darkened bars and warehouses to homes, hospitals and office buildings.
"The illumination is as bright as one of the new high intensity auto headlights, but portable," adds Jones. "In a bedroom fire with extremely thick smoke, I had very good visibility at least 5 feet in front of me with the Recoil LED flashlight. I could see books, clothes, a laundry basket on the floor. Seeing with that kind of detail is especially important when searching under a bed where children usually hide in a fire. It allows you to see from one side of the bed to the other, which can be critical in smoky search and rescue operations."
Garcia concurs, "The new flashlights focus bright, shadow-free illumination exactly where you're pointing. They penetrate smoke, steam, dust, or fog so we can quickly find those who need help, or clearly signal to others at a distance. Their energy efficient LEDs provide far longer bulb and battery life than traditional lights."
The Journey from Incandescent to LED Lighting
It's hard to imagine that the light bulb, an invention that ushered in the Industrial Revolution, has remained basically unchanged for 124 years. In modern incandescent lighting, electricity still heats a tungsten filament inside a glass bulb – as it did in Thomas Edison's time – until the tungsten gets "white hot" and emits visible light. Incandescent bulbs today remain tremendously energy inefficient, with just four to six percent of the electrical power supplied to the bulb converted to visible light.
The halogen light used in most flashlights also uses a tungsten filament, but enclosed in a much smaller quartz bulb. Halogen bulbs emit more light than standard incandescent bulbs, but they are also extremely energy inefficient, often burning out after only 50 hours of use.
"Traditional halogen bulbs burn hot, quick, and are quite fragile," says Jones. "They don't hold up well to the shock of being dropped, the heat of fire, the water of fire suppression, or rattling around inside the truck. But in fire service, we need reliability."
Moreover, in flashlights, both halogen and incandescent bulbs cast a washed-out oval-shaped pattern of light known as the "fisheye effect." This is due to scattered peripheral light reflecting imperfectly forward off the flashlight reflector.
As an alternative, newer and cooler light sources such as light-emitting diodes (LEDs) are not only more energy-efficient, but also sturdier and more compact. Due to its energy efficiency and longevity, LED technology has already been applied to create a generation of LED flashlights. However, existing LED flashlights cast only a wide, diffused beam capable of illuminating objects only a few feet away.
While conventional incandescent and LED flashlights shine light imperfectly forward with scattered peripheral light, recoil LED technology for flashlights takes the opposite, counterintuitive approach. Like a lighthouse, the new technology focuses light by firing it backwards. A special parabola-shaped reflector then captures 100 percent of the light and reflects it forward.
The resulting parallel-focused beam of light is free from scattered peripheral light, greatly increasing its ability to cut through obscure environments like smoke, steam, vapor and dust. Since there is no filament involved in the process, the bright white, color spectrum-tested light is also free of the annoying black spots, shadows and distortion found in traditional filament-based lighting, which can never completely mask filament shadows or a distorted oval pattern of lighting.
"What the new flashlights do," says Jones, "is improve our ability to operate in the field. They cut through smoke with regular white light to help us better and more quickly gauge our surroundings. With a more effective tool, we'll be able to do a more effective job. The end benefit will be more saved lives and less property damage, with fewer wasted man hours replacing flashlight bulbs and batteries in the field."
For more information about Recoil LED Technology or its use in flashlights, visit www.pelican.com.
Del Williams is a technical writer based in Torrance, Calif.