Building Construction, Codes & Standards, Firefighting

Keeping Up with Technology Revisited: Impact-Resistant Products

By Ric Jorge

“If you haven’t come up against impact-resistant products, you’re in for a rude awakening.” That was my opening statement in an article I wrote for a Florida publication in 2004, and I still stand by it. In the past seven years, I have witnessed this industry explode and spread at a rate usually reserved for wildland fires. This article is intended to raise awareness about products you may have given little consideration to because of your geographical location. This is not just a Florida thing anymore; this is a national trend, and the impact they can have on firefighters will be fatal if we do not prepare accordingly.

In Florida, these products gained popularity because of our exposure to hurricanes and tornadoes, but it was not until 2003, at Melbourne Fire Academy, that I was exposed to the first impact glass I had ever seen. Jerry Jensen of the Sarasota County (FL) Fire Department showed one during a lecture. It was there that I also obtained a video (created in 2001) by Mike Hartley and John Elwood (both of Sarasota County Fire) in conjunction with PGT® windows that demonstrated the strength of these windows. Since that time, I have made it my business to know as much as I can about these products.

Impact products of all sorts, not just windows, can be found in residential, commercial, and high-rise buildings across the country. The U.S. government is retrofitting all government buildings (including U.S. embassies overseas) with these products as well as all military buildings/installations. Currently, the Centers for Disease Control and Prevention headquarters in Atlanta is being retrofitted. In Florida, it is part of the Building Code standard 1609, 1626 for new and existing structures that are determined to be in the “wind-borne debris region.” The insurance company enforces compliance, which is reflected in your homeowner rates.

I will use the term “impact” to identify products found in today’s market for wind-loading (pressure) as well as impact (debris) rating. Impact-rated products come in various forms such as windows, doors, garage doors, shutters, roofing material, and even new wall construction.

New wall construction is merely a variation of tilt wall construction used in the residential market, which allows homes to withstand significant wind and impact loads over concrete block structure (CBS) or wood frame. This type of construction has variations throughout the country. Styrene is being employed with rebar and concrete to increase the R* value (a measure of thermal insulation) and water resistance factor. What differentiates this type of construction for firefighters is the degree of difficulty in breeching these walls as opposed to conventional CBS or frame types of construction.

Windows and doors (including garage doors) receiving a state (for example, Florida) mandatory impact rating at a hurricane testing laboratory (HTL) must withstand several types of tests. Testing is broken into categories according to the rating a product must achieve. A hurricane rating is broken into three tests.

1. Impact test: Done by shooting large or small objects at the window.
2. Rain test: Eight inches of water per hour at 110 to 120 miles per hour.
3. Air leak test: A cyclical pressure test lasting five hours.

To obtain a “multihazard-mitigation” designation, the product also has to undergo additional tests:

1. Fire: Testing is a one-hour fire rating.
2. Bomb: Testing is rapid pressure build followed by debris (large and small).
3. Hurricane: The first three tests (impact, rain, air leak).
4. Tornado: A test is done with large debris with little or no pressure

A fire bomb-hurricane (FBH) certification includes all of the above stated tests, and can come in the form of a 9/16-inch window with a polycarbon membrane. Although this glass is impressive, the frames are even more formidable. The frames are manufactured in such a way that they interlock, giving them the strength to survive the testing. They are then attached to the building every eight to 12 inches. Attempting to “clean a window” can no longer be done using a hook or halligan–a saw is required to accomplish this task quickly and cleanly. The modern-day impact window is 10 times stronger than the windows of 20 years ago, and covers a broader spectrum of uses. The heaviest concentration of these products is found along the eastern seaboard, but these products can be found all over the country, touted as security products. 

These products create more than just a breaching issue for firefighters. The box has gotten significantly tighter, which means the heat will be retained during fire; the smoke will not issue forth as we are accustomed to seeing, making “reading” it more of a challenge; and the flow path has the potential to be much more defined and dangerous. Now more than ever, the need to know before you go is critical, because our margin for error in these buildings is far less than traditional training has taught us.

Ric Jorge is a firefighter for Palm Beach County, Florida, since 1992. He is assigned to the 3rd Battalion at Station 33. He is a State certified instructor and live fire instructor. He teaches at Palm Beach State College and throughout Florida. You can reach him by e-mail at [email protected]

Ric Jorge will be teaching “Ventilating Impact Resistance Coverings” at FDIC 2012 in Indianapolis, Indiana. For more information or to register for FDIC, go to https://www.fdic.com/attend/conference/classroom-sessions.html.