The Heat is On: Fire Fuels Research at FPL

Where there’s smoke, there’s fire — but where there’s wood, there’s always the chance of fire. Luckily, where wood and fire meet, there’s the Building and Fire Science work unit at the Forest Products Laboratory (FPL).

This CLT specimen survived almost 100 minutes of exposure in a standardized test reaching nearly 1000°C. The unexposed side of the specimen remained at less than 50°C for the entire test.

Throughout its existence, FPL has long been on the cutting edge of fire science. Fire prevention will continue to be a major area of study as wood expands into commercial and high-rise construction.

This unit is charged with researching how wood and fire interact, and help make wood products more fire resistant and in compliance with international fire safety standards. One way to accomplish this daunting task is through the use of flame-retardant treatments (FRTs) — but what exactly do these treatments do?

FPL Research General Engineer Mark Dietenberger, and Laura Hasburgh, a Fire Protection Engineer at FPL, know exactly how FRTs work. Their recently published document Wood Products Thermal Degradation and Fire in the Materials Science and Materials Engineering Reference Module for Elsevier takes an in-depth look at these treatments and explains how they work to keep wood from going up in flames.

Most FRTs delay ignition, reduce heat release, and reduce flame spread. Other possible mechanisms for fire retardancy include conducting heat away from the heat source, endothermic chemical reactions to absorb heat, or the releasing radicals that inhibit combustion. Some flame-retardant coatings can even swell to form an expanded low-density protective film for the material upon exposure to fire. These FRTs are known as intumescent formulations.

For interior applications, Dietenberger and Hasburgh note that water-soluble inorganic salts are the most common flame retardants. These chemicals are combined by researchers in specific ways to optimize a material’s fire performance and reduce individual aspects of a fire. Boric acid, for example, can be added to an FRT formulation to reduce smoldering or glowing.

hrc

FRTs can reduce the heat release characteristics of wood. Above are heat release curves for untreated and FRT Douglas-fir plywood.

Although the FRTs decrease the flammability of a material, they can increase other dangers associated with fire, like the production of smoke or weaken a material’s structural integrity. Fire retardant-treated wood is often more brittle than untreated wood, and some FRTs can cause further losses in strength with continued exposure to elevated temperatures, for example, the roof of a burning building.

FRT research thus is a delicate balancing act, and researchers strive to create FRTs that allow wood to remain both strong and fire-free. Though the heat is on for the men and women from FPL’s Building and Fire Science unit, they have proven they are up to the challenge — continually pushing the limits of FRT with every experiment, and helping to make our wood, and us, safer.

For more information, please see the full article, Wood Products Thermal Degradation and Fire.

Be Good to Your Christmas Tree And it will be good to you ...

TREE

Each year over 30 million Christmas trees will be sold in the U.S. Mother Nature’s kind. The real, beautiful, ever-green, ever-aromatic centerpiece of our holiday season. They will dress up our houses and maybe most important, will be the landing point for all manner of goodies when Santa pays his annual visit — assuming, of course, we were good this year.

Which is why it is vitally important to take good care of your tree, because a tree that goes unloved and uncared for can be deadly. We don’t want to throw water on the celebration, but facts are facts. Actually, maybe we do want to throw water on the celebration, or at least at the tree.

Simply keeping your tree properly watered significantly decreases the chances of a catastrophic fire in your home. Not convinced? Take a few seconds to watch this eye-opening video courtesy of the National Fire Protection Association. Wow.

While you’re at it, try to spend a few more minutes looking through these excellent basic tips for proper tree care brought to you by Purdue University.

If you don’t have a few minutes the easy-to-follow instructions below could mean the difference between a joyous holiday season and a really, really bad one.

  • Find a tree with pliable needles that stay on the branches.
  • Cut 1/2 inch from the end of the trunk, and use a tree stand that can hold plenty of cool water.
  • Water often. Be sure to keep the water level above the tree base, otherwise the end of the tree will seal, preventing additional water from entering the tree.
  • Keep the tree at least 3 feet away from any heat source and don’t let it block any exits.
  • And it goes without saying that candles should never be used on or near the tree.

And stop by our website for more information about past and present fire safety research at FPL.

Be safe and enjoy your tree!

Fire Safety for New Wood Products FPL's History in Fire Research

A compelling issue at FPL is how we ensure that traditional and new innovative wood products do not adversely contribute to loss of life and property in fires.The Durability and Wood Protection Research at FPL is prepared to answer these questions. A part of the group’s mission is improving durability and wood protection through improved building design, advances in low-toxicity wood preservatives, and improvements in fire safety.

With unique fire research facilities, fire safety research at FPL addresses the potential contribution of wood products to the growth of a fire, the ability of structural wood elements to withstand a fire, and the chemical treatment of wood products to reduce their flammability. Fire safety is a major component of existing building codes and will be continue to be so in future developments of editions of the building codes and other regulatory documents.

flashpoint

This burning test structure from 1975 is at the point of flashover—the sudden spread of flames over an area when it becomes heated to the flashpoint. Results of these tests indicated that sandwich panels provided structural integrity for various lengths of time depending on the facing material used for the panels.

FPL has worked on fire safety for decades and has helped quantify the fire performance of wood products. This research has contributed to the development of treatments of wood that reduced their flammability. Research helped define the fundamentals of fire behavior and efforts to develop methodologies for fire testing of wood and composite materials to ensure proper measurements of relevant performance characteristics. More recently, contributions have been toward data and models required for fire safety engineering of forest products in a performance-based building code environment.