When customers and employees leave the building after business hours, the electronic metal curtain above the main entrance will totally enclose and secure the structure.
Photo credit: Photo by William R. Mora
Light, moderate or heavy smoke showing on arrival, are signs of extremely dangerous conditions that may cause prolonged zero visibility, flashover, backdraft or indicate the potential collapse of floors or roofs.
Photo credit: Photo by William R. Mora
After arrival and for safety, firefighters should slow the action down and follow a flexible guideline, programmed to avoid the risk, when encountering large enclosed structure fires.
Photo credit: Photo by William R. Mora
Contrary to the faster tempo traditionally utilized at opened structure fires, for safety, firefighters operating at the scene of an enclosed structure fire must slow the action down after arrival and fully anticipate the potential danger associated with the enclosed structure. Firefighters also are to resist the impulse to charge into the structure, without making an accurate enclosed structure size-up; even though the heat and smoke may indicate that the structure is tenable. Taking a slower, more calculated approach, is highly recommended in the effort to prevent a disorientation or fatality sequence from unfolding. In other words for safety, learn from the past and do not allow adrenalin or the repetitive standard use of opened structure procedures to control the action at an enclosed structure fire.
When larger enclosed structures are encountered it is important for all responders to fully understand and to follow a flexible guideline programmed to avoid the danger. For safety and task predictability, the Enclosed Structure Standard Operating Guideline (SOG) should be implemented in the sequence of company or resource arrival. This allows the pre-determined action plan to be placed into motion with minimal confusion and allows the incident commander to continue the size up process, to serve as a facilitator, to anticipate potential hazards, the need for additional resources and to monitor the companies as the guideline is implemented.
One of the most important operational rules firefighters must also understand is that safety, not speed of execution of tactics, is what is ultimately sought during an enclosed structure incident. In addition, all firefighters must follow their department's risk management statement which should indicate that firefighters are not to needlessly risk their lives to save a structure or a victim who is not viable. However, firefighters can take calculated risks to save victims who can be saved. Sound firefighting principles and nationally recognized safety standards and procedures, including utility, traffic and crowd control, use of an accountability system, preplans and of the incident command system, are also presumed to be utilized during the safe implementation of an enclosed structure SOG.
Traditional Size-Up No Longer Useful
In addition to the possible life hazard present, many critical factors are routinely considered during an initial size-up and throughout the course of a structure fire. During this rapid initial evaluation, factors observed will warn firefighter's of existing or impending danger. These factors include:
- The type of occupancy
- The type of construction
- The condition of the structure
- The amount of smoke and fire showing
- The size and age of the structure and others
However, despite warnings provided by these traditional factors, traumatic line-of-duty deaths in structural fires continued to plague the fire service. Analysis of the disorientation study showed that firefighters at enclosed structure fires clearly and confidently took action based on a traditional size up, established procedures and sound firefighting principles. However, safety was still compromised resulting in unfavorable outcomes.
Enclosed Structure Size-Up
A critical and complex safety issue dealing with the misinterpretation of initial size-up factors will exist during the early stage of an enclosed structure incident. Although traditional size-up factors do accurately warn firefighters of the danger at opened structure fires, they may not at enclosed structure fires. Light, moderate or heavy, but tenable smoke showing from an opened structure may indicate that it is safe to make a quick and aggressive interior attack, but during the course of an enclosed structure fire the factors may have a completely opposite meaning indicating that conditions are extremely dangerous. Since this misinterpretation has been a serious area of confusion, officers and firefighters must be aware of the special attention needed with the critical and variable initial size-up situation described and summarized below.
Small manageable fires will obviously continue to occur in enclosed structures and will continue to be safely extinguished by investigating companies without difficulty. The ultimate challenge for arriving firefighters, however, will be to distinguish between a nuisance fire producing light or moderate smoke and a classic enclosed structure fire which will also produce identical smoke conditions but that has the potential to result in life threatening hazards leading to firefighter fatalities.
Primary Search at Large Enclosed Structure Fires
On arrival and prior to implementing the guideline, the first arriving officer assumes command, reports the conditions and communicates that a large enclosed structure is involved. The officer will then determine the need to conduct a primary search. When informed and confirmed by a credible person that a true rescue of a savable victim is required, it should be conducted by firefighters avoiding, to the extent possible, the known risks associated with the enclosed structure. This will require quick development of a calculated rescue action plan which should include at minimum: determining the last known location of the victim, use of thermal imaging cameras, avoiding a collapse of floors or roofs, approaching the victim using the safest and shortest distance from the exterior, and simultaneously and aggressively attacking the fire to prevent a flashover which may engulf both victim and rescuers.
However, it is also critically important to note that as large enclosed structures usually involve non-residential structures, the need to actually conduct a patterned, "room by room" primary search for victims of a large enclosed structure has not been observed. However, there have been cases where occupants of warehouses, grocery stores and other large businesses exited under their own power. In other cases, occupants exited the structure prior to firefighter arrival. And in still other cases, the large enclosed structure was found to be unoccupied or vacant. Additionally, in many situations a rescue will simply not be required as the fire will occur after business hours and the structure will be locked or secured with security bars or gates. In cases involving enclosed structure fires occurring during business hours, the owner may also approach and directly inform one of the first arriving officers that everyone has exited the structure. This key information must immediately be passed on to all responding companies to prevent conducting an unnecessary and dangerous primary search.
Special thanks to: The National Fire Data Center; U.S. Fire Administration and The National Institute for Occupational Safety and Health Firefighter Fatality Investigation and Prevention Program
- Enclosed Structure Standard Operating Guideline (SOG)
- U.S. Fire Adminstration Firefighter Fatalities Homepage
- United States Firefighter Disorientation Study 1979-2001
William R. Mora has dedicated 32 years to the San Antonio, TX, Fire Department as a firefighter, engineer, paramedic and training officer. Captain Mora is currently assigned to the firefighting division. He serves on technical advisory boards for the University of Kentucky, Lexington and has studied educational methodology and hazardous materials in depth at the National Fire Academy.
Captain William Mora is a fire consultant with an interest in firefighter safety, strategy and tactics, standard operating guideline development and firefighter disorientation. Captain Mora has advanced new firefighting terminology, tactics and concepts to help firefighters recognize, manage and avoid the risk at structure fires. He has been published on the topic of firefighter disorientation and enclosed structure tactics in Firehouse.com, Fire Chief Magazine, and Fire Engineering Magazine, as well as in the National Fallen Firefighters Foundation Everyone Goes Home Newsletter. He has given presentations on the prevention of firefighter disorientation for the Fire Department Instructors' Conference, Texas Volunteer Fire Departments and for the Maryland State Firemen's Association.
The firefighter disorientation problem has compelled Captain Mora to provide assistance to fire officials, safety educators, grant writers, and fire industry professionals with valuable researched information. He has been active in the effort to prevent firefighter disorientation and traumatic structural firefighter fatalities. Working towards that goal, Captain Mora conducted an analysis of 444 structural firefighter fatalities, identifying a large percentage of line-of-duty deaths occurring at enclosed structure fires where offensive strategies were used. He served as a participant at the 2004 and 2007 National Fallen Firefighters Foundation Life Safety Summits and currently serves as an advocate for the Everyone Goes Home Firefighter Life Safety Initiatives Program for the state of Texas. Captain Mora is the author of the United States Firefighter Disorientation Study 1979-2001 which appears in the United States Fire Administration's annual report: Firefighter Fatalities in the U.S. in 2003, 2004 and 2005. You can contact William by e-mail at: firstname.lastname@example.org.