What is in this article?:
NIST researchers recently conducted a series of tests to study the effects of various firefighting techniques to prevent flashover -- and the results could alter the future of fireground tactics.
(Appeared in print as "Game changer")
Chief officers face tough questions about what we do on the fireground and why we do it — especially when a firefighter is injured or killed. But it’s important to understand that today’s fires aren’t the same as the ones chiefs once fought as firefighters.
Research shows that modern furnishings, construction components and other factors have changed how fires burn. Firefighters must have the latest information to hear what a fire is saying and how best to extinguish it.
Indeed, a new research study conducted by theis giving the fire service a lot to talk about.
“We finally are listening to the fire — what will it have to tell us?” asked Phoenix Fire Chief Alan Brunacini (Ret.) about the tests.
The testing environment
In January, NIST researchers and volunteer and career firefighters conducted a series of tests in Spartanburg, S.C., to study various suppression methods — individually and in combinations — for ventilating and isolating fires to prevent — or at least delay — flashover. Firefighters from 15 states and the District of Columbia participated in the burns, which were funded by a $619,000 FIRE grant awarded to the ISFSI.
More than 160 fire-service officials from across the country, along with elected officials, public-works partners and a fifth-grade class attended the demonstrations. Such an open-door policy ensured maximum exposure to this information.
The burns were conducted in eight homes already slated for demolition. The houses were of older construction, but they did feature newer windows and modern furnishings. Each of the houses was furnished with the same pieces: a couch, two chairs, coffee table, end tables and lamps in the living room and a queen-sized bed, dresser and night stand in the bedrooms. The houses also featured heat-measuring devices and high-heat thermal cameras.
Also inside some of the houses were simulated firefighters wearing full gear to see if human firefighters would survive conditions based on the tactics used.
This research continues to build on the work already conducted by NIST and Underwriters Laboratories. What made Spartanburg different was researchers’ focus on single-family detached dwellings.
“This is the first time we’re looking at how older homes with new furniture and windows burn,” Dan Madrzykowski, NIST research team leader, told the media after the burns. “Now, lot sizes are a lot smaller, so houses are closer together and there are more open spaces so fire moves more quickly than fires we had, say 20 years ago.
“Some of grandad’s (firefighting) tactics haven’t held up,” he said, because of the plastics and fuels from crude oil found in homes.
The first-due company officer to a single-family detached dwelling — whether its 1,000 square feet or 10,000 square feet — should evaluate the strategy of limiting air by controlling the flow-path and getting water into the space where the fire appears. If the fire appears confined in the space and has not extended into the attic, the initial application of water from a non-IDLH position will reduce the temperature.
This isn’t to say that firefighters should not enter a burning building, just that it doesn’t cause harm to put water on the fire while firefighters are outside the structure. Spraying smoke may be just enough to prevent flashover, because if firefighters can limit the air supply to the fire, they have a better chance of controlling it.
Applying water into the fire space results in a greater than 750° temperature reduction, regardless of how the water is applied. Opening doors and windows on a house that has a ventilation-limited fire will increase the temperature, which can make fuels ignite almost immediately in an environment that previously wouldn’t have supported combustion.