You don’t have to look very far on the Internet to find firefighters in rapidly deteriorating fire situations when conducting interior fire attack and roof operations. The National Institute for Occupational Safety and Health reports are plentiful of such examples. I won’t focus on why roof operations are important or how they should be accomplished but rather on developing your ability to read “red-flag” warning indicators before sending firefighters onto a questionable roof.
You must be situationally aware of key risk factors to make better decisions about placing firefighters on a potentially fire-weakened roof. If you don’t understand the risk, you can’t effectively manage the risk. Just as reading, writing, and arithmetic were the foundations of education, a great foundation for risk management are the “3 Rs” of size-up: reading the risk, reading the structure, and reading the smoke.
On April 3, 2016, the Greenville (TX) Fire Department was dispatched to a kitchen fire on the second floor of a two-story apartment complex built of wood-frame construction. Although the kitchen fire was contained quickly, it had already extended into the ceiling space above. Unknown to firefighters initially, this structure’s original roof was a flat, built-up roof; a secondary gabled roof built of lightweight wooden truss construction had been added over the existing flat roof years later. This created a void space above the flat roof that was inaccessible from below.
(1) Firefighters attempted to access the fire below the peaked roof. [Photos courtesy of the Greenville (TX) Fire Department.]
During firefighting operations, two firefighters were injured when one firefighter fell through the peaked roof while attempting to access the fire from above. A second firefighter was also injured while assisting the first firefighter from the breached location. Both firefighters were able to self-extricate. At the same time this Mayday situation was occurring, the fire became wind-driven from the gable (windward) end of the roof, following the flow path to the peak, where heavy fire erupted as a result of burn-through of the peaked roof. As the two injured firefighters were climbing down the ladder, the roof began to collapse.
Reading the Risk
A primary risk factor to consider prior to allowing crews to operate on the roof is whether or not the fire has weakened the structural support system. Significant or heavy fire involvement of the structure’s attic or floor void space is a red-flag warning sign for firefighters and a critical development for which the incident commander (IC) must be alert and advised on. I have witnessed well-intentioned firefighters going onto a roof built of lightweight wood-frame construction of a heavily involved, self-vented attic fire to conduct roof operations. Frankly, there’s a real problem with that! Firefighters have lost their lives falling through these types of lightweight engineered wooden roofs because of poor decision making, complacency, and lack of understanding of the risk involved.
Don’t get me wrong: Traditional or legacy wood-frame construction will maintain its integrity under fire conditions for a longer time than a lightweight engineered wooden roof, but fire spread into the attic or floor void space does not necessarily create a no-go situation for firefighters. It indicates that a dangerous fire situation may be rapidly developing, which could quickly pose an unacceptable danger to firefighters, especially if the structure is built of modern engineered wood-frame construction. Today’s engineered wood-frame structural components lack the mass of legacy wood-frame construction. The more mass or bulk the structural wood-frame component has, the greater or longer its ability to withstand or remain structurally sound under fire conditions (i.e., Mass = Time).
(2) Minutes later, firefighters were injured after falling through the peaked roof
(3) Heavy wind-driven fire involvement of the roof occurred less than a minute after firefighters self-extricated.
Aggressive firefighting tactics are the gold standard for offensive firefighting operations. However, it’s a matter of risk vs. gain, knowing when and where to be aggressive and when and where not to be so aggressive. Any type of roof support system that is heavily involved and has fire venting through the decking is a major safety concern. A building that is a total loss when you step out onto the roof is still going to be a total loss when you get off.
Risk factors. Following are several risk factors to consider:
- Know the location and extent of fire spread into a void space below the roof and floors, and communicate this to the IC. A floor or roof deck may appear to be stable on entry and then completely fail moments later. There is no margin of safety once the fire enters the void space.
- Be aware of changing wind conditions. Prevailing winds of 10 miles per hour or greater entering the structure through any upwind openings, such as failed windows, doors, or soffits, can produce a wind-driven fire condition that can immediately trap unsuspecting firefighters with little or no warning and hasten the failure of the roof’s structural integrity.
- “Reading the risk” should include overhaul operations. Firefighters have needlessly died or suffered career-ending injuries after falling through a fire-weakened roof of a totaled-out structure during overhaul because of a willingness to take an unacceptable risk, lack of awareness of the structural dangers, complacency, fatigue, or failure to follow department standard operating procedures (SOPs) for roof ladder or aerial platform use.
Reading the Structure
Every firefighter should understand the unique structural dangers posed by the types of building construction, especially legacy vs. modern wood-frame construction, and how notoriously fast modern wood-frame roof and floor support systems can fail when exposed to fire. Modern wood-frame construction is found widely in today’s homes, apartments, commercial occupancies, and fast-food restaurants. These structures have become “disposable” and are no longer built to last a lifetime like those built in the first half of the 20th century.
Today’s engineered wood-frame construction components have been used increasingly since the 1970s and pose a much greater risk to firefighters when exposed to fire than the previously used legacy construction methods. Engineered wood-frame construction is a key indicator fire officers must not ignore during size-up.
Following are several structural risk factors to consider:
- Know the type of construction involved—legacy vs. modern wood-frame construction (or a combination of both)—and how it can kill you.
- Note the age and physical condition of the structure. Look for secondary roofs and renovations over the years that may create inaccessible void spaces where fire can burn unchecked. This is why it is so important to get out into your response district as a crew for familiarization on a regular basis.
- Consider the live and dead load factors on fire-weakened roofs such as air-conditioning units and the firefighter weight load on an already fire-weakened roof.
- Look for structural features that can help or hinder your operations such as fire walls or an adjoining roof that may serve as an area of refuge. Do not overlook the presence of parapets and the risk they pose to firefighters. Consider the building’s contents related to fire load and any process hazards that may be present within the structure. This is where preincident planning is an invaluable tool.
Reading the Smoke
Often, the smoke showing from a building fire on arrival may be the only clue available to help you answer three important questions: (1) Where’s the fire? (2) How big is the fire? and (3) Where is the fire going? Your ability to read smoke helps to answer these three important questions. This is especially important if you are considering sending crew members to the roof to ventilate.
Aggressive firefighting has been a hallmark of the American fire service. Today, we must base the concept of aggressive roof operations on an understanding of fire dynamics and building construction. Fire officers must understand this concept and be able to predict what the fire and the building will do before committing firefighters onto the roof. Because 21st century fuel loads and building construction materials continue to evolve, the net result is faster developing fires, faster time to flashover, less time for occupants to escape, less time for firefighters to make entry to find victims, and faster failure times for roof and floor assemblies.
Tactical Considerations for Success
Following are 10 tactical considerations for safer roof operations.
- Is there an actual need to even conduct roof operations? Sometimes, going to the roof is the result of reactive rather than proactive thinking.
- If there are no hoselines in place at or near the seat of the fire, this is a caution sign.
- Always be able to communicate with the fire attack crew.
- Know the signs of a weakening roof—i.e., lightweight construction with significant fire underneath the deck, growing vent pipes, a sagging deck, bubbling tar, fire burning through the roof decking/eaves, or multiple layers of roofing material present.
- Never cut the roof and create an opening that blocks firefighters’ escape routes.
- Always set secondary escape ladders.
- Do not place too many firefighters on the roof. Limit the number of personnel on the roof to only what is needed for the job.
- Assign a lookout or safety person. The roof officer should avoid being involved with the hands-on portion of the operation and must continually watch for changing fire conditions. When changing fire conditions are noted, take a tactical pause, reevaluate, and reassign as needed.
- When ventilating, once the task is completed, get off the roof!10. Do not permit firefighters to remain or go on to the roof during defensive firefighting operations.
Vertical ventilation or trench cuts are performed to support offensive fire attack operations. When you declare defensive operations, clear the roof of personnel immediately and establish and enforce a collapse zone.
Remember, size-up is a continuous process until the incident is terminated. What are your “trigger points” in determining whether or not you can safely conduct or suspend roof operations? The skill of the 3 Rs is only sharpened through use.
GARY BOWKER is an honorably retired U.S. Air Force master sergeant and has served as a fire chief at numerous U.S. Air Force bases around the world. He has also served as chief of the Sumner County (KS) Rural Fire District #10. Bowker is a retired fire marshal and safety officer with the town of Winfield, Kansas, and has more than 45 years of fire service experience. He has also taught numerous courses for the National Fire Academy, the U.S. Department of Defense, the University of Kansas Fire & Rescue Training Institute, and FDIC International. Bowker also serves as a Kansas advocate with the National Fallen Firefighters Foundation’s Everyone Goes Home program and speaks frequently at events. He has written numerous articles on firefighter life safety and health issues and has been published in numerous fire service trade magazines. Bowker is nationally certified as a fire officer II, instructor II, and inspector II and is a certified fire and explosion investigator.