Firefighter disorientation -- loss of direction due to the lack of vision in a structure fire -- is one of the oldest, least understood and deadliest hazards of interior firefighting. However, with training, it can be prevented.
United States Firefighter Disorientation Study 1979-2001, which I published in 2003, examined 17 fires that occurred across the country. It revealed that in every case, disorientation occurred when firefighters conducted fast and aggressive interior attacks into enclosed structures and spaces. These actions resulted in the deaths of 23 firefighters. It is my contention that by understanding what happened at these fires, the disorientation problem in the fire service can be eliminated. This can be accomplished partly by grouping and managing enclosed structures, much as we categorize hazardous materials, and by using new tactics and new and existing terminologies. Additionally, properly trained first-arriving officers will be able to identify enclosed structures during initial size-up and know when to use a different approach to safely and effectively manage these incidents.
Opened vs. Enclosed Structures
An "enclosed structure" has few readily penetrable windows or doors for prompt ventilation and emergency evacuation. These structures can be of any type of occupancy, any type of construction, any size, age or configuration and can be occupied, unoccupied or vacant during a fire. They include enclosed spaces such as basements and high-rise hallways. But the single common identifiable thread is that they are enclosed. These structures exist in every community and will be a major structural firefighting problem for decades to come.
A certain type of firefighter disorientation also occasionally occurs in what are referred to as "opened structures." This typically involved disorientation caused by the blinding effects of a flashover. Opened structures are small to moderate in size, built on a concrete slab foundation having an adequate number of readily penetrable windows and doors for prompt ventilation and emergency evacuation. Opened structures should be considered dangerous to firefighters, meaning occasionally fatal, while enclosed structures should be considered extremely dangerous because of their record of disorienting and repeatedly claiming the lives of firefighters. Although firefighters already know that any structure on fire is dangerous, they can also know which specific type of identifiable structure is extremely dangerous -- and why. When routinely applied on the scene, this fact alone can provide firefighters with a simple early warning that can prevent fatalities.
In any tragedy, there will be a chain of events that leads to an unfavorable outcome. If, however, a link in the chain can be broken, a loss such as a fatality can be prevented. In structural firefighting, one such chain is the firefighter disorientation sequence. Since the sequence frequently leads to the killing of one or even multiple firefighters at single events, it should clearly be understood by every firefighter.
The steps of the sequence are:
- Fire in an enclosed structure with smoke showing.
- A quick and aggressive interior attack.
- Deteriorating conditions.
- Handline separation or entangled handlines encountered.
Although the sequence is straightforward, firefighters must also be aware that on occasion it can unfold fatally "out of sequence." For example, handline separation taking place as a result of firefighter failure to maintain contact with a handline, regardless of the reason, can occur before conditions within an enclosed structure begin to deteriorate. Once conditions deteriorate, with development of prolonged zero visibility conditions, for instance, the sequence is completed. Therefore, although the sequence is not in chronological order, it will have equally fatal results -- a sequence that occurs in a 1-2-3-4-5 progression is just as deadly as one that occurs in a 1-2-4-3-5 arrangement. This phenomenon played out at large enclosed structure fires in Worcester, MA, Chicago, IL, Kansas City, MO, and most recently in Charleston, SC.
It is important for firefighters to realize that disorientation is, in fact, only an interim step that may or may not lead to fatality. Many factors play into whether a firefighter fatality occurs in an enclosed structure; here are just a few: Should a disoriented firefighter who is not deep in the interior of a structure call a Mayday and receive assistance in a timely manner, chances are the firefighter will survive. If, however, a disoriented firefighter is unable to obtain immediate and invasive help or fails to self evacuate prior to depleting the air supply, the firefighter will die. The same holds true for a firefighter engulfed in a flashover or a backdraft. If the firefighter is unable to quickly locate a means of egress through the blinding and painful exposure to fire, the distressed and disoriented firefighter will also perish. One can see that the same fate holds true if the firefighter drops through a fire-weakened floor and into an involved basement (enclosed space) or is pinned down by a collapse of a roof. When these associated structural failures blind firefighters, separate firefighters from handlines and expose firefighters to life-threatening danger, the result will also be the same. Therefore, for safety, the best alternative to take during enclosed structure fires is to use a tactical plan carefully designed to avoid the danger.
The ways in which firefighters lose visibility in structure fires represents one of the more complex aspects of firefighter disorientation. Although it is easy to understand that heavy smoke can cause the blindness that results in disorientation during fires in enclosed structures and enclosed spaces, firefighters in the study lost visibility five different ways. The resulting disorientation occurred following exposure to life-threatening hazards, some of which rapidly engulfed or exposed attacking or evacuating firefighters, while others deviously and fatally developed gradually.
The five types of firefighter disorientation identified include:
- Disorientation secondary to flashover.
- Disorientation secondary to backdraft.
- Disorientation secondary to prolonged zero-visibility conditions.
- Disorientation secondary to collapse.
- Disorientation secondary to conversion steam development.
Experienced firefighters understand that strenuous work must often be accomplished in periods of zero visibility. Zero visibility occurring in opened structures is dangerous, but usually does not result in sustained disorientation and death. This is because, as defined, opened structures provide windows and doors that are adequate in number and large enough for all firefighters to bail out of while dressed in full turnout gear. These windows and doors are critical because they let firefighters promptly ventilate and evacuate should interior conditions rapidly deteriorate. Zero-visibility conditions are defined as those that cause blinding conditions for 15 minutes or less. This corresponds to the effective breathing time a 30-minute-rated air tank will provide a working firefighter.
Although a firefighter may become disoriented in an opened structure, such disorientation is usually temporary, lasting until effective ventilation allows visibility to be regained within the interior of the structure. Due to the smaller size of the structure and the availability of walls to assist in exiting and with availability of penetrable windows and doors, firefighters are more capable of reaching a means of egress. The opposite, however, is true of enclosed structures and that is why they are extremely dangerous.
Since very few windows or doors that are readily penetrable exist in an enclosed structure, zero-visibility conditions become and remain prolonged. Once visibility in an enclosed structure drops to zero, any firefighter in the structure or who enters the structure will be operating in a sustained zero-visibility environment for the duration of the fire. This is an extremely dangerous, unfamiliar and, at times, terrorizing condition for the unsuspecting firefighter to experience, usually leading to panic, accelerated rate of respiration, rapid depletion of air supply, calls for Maydays and death by asphyxiation.
Prolonged zero-visibility conditions are blinding smoke conditions that last 15 minutes or greater. More simply, it can be regarded as a time span that exceeds a firefighter's breathing capability while in a structure. Prolonged zero visibility must be recognized by the fire service as a life-threatening condition that can develop at different rates of speed to deviously endanger even veteran firefighters.
Life Lines and Misread Size-Up Factors
With history as evidence, firefighters cannot continue to use an offensive strategy at an enclosed-structure fire and expect to survive. The tactics simply may not work. In addition, the need to maintain close proximity to, or constant contact with, a handline, in particular, cannot be emphasized enough when working in the interior of an enclosed structure. This issue is so serious that the use of a hand-line at enclosed-structure fires to serve as a "life line" out of the building should be mandatory in every fire department. The concern that adequate numbers of handlines are not available to allow every engine and truck company to have one is not valid, as evolutions currently exist that routinely provide all companies with protection with 1Â¾-inch handlines against rapidly changing conditions or to serve as life lines whenever needed.
Another complex aspect that leads to disorientation is that handline separation may also occur in various ways and related to the effects of a flashover, a backdraft, or a collapse of a floor or roof. Handlines have also been inadvertently removed from structures prior to conducting personnel accountability reports (PARs). It can also innocently occur at the start of an incident. This often occurs due to misreading of initial size-up factors. Firefighters, accustomed to opened-structure tactics, have mistakenly thought that use of a handline as a life line was not necessary when they entered an enclosed structure because light smoke conditions observed at the beginning of the incident did not translate into an extremely dangerous condition. However, when conditions deteriorated, the lack of a handline completed a disorientation sequence that resulted in fatality. Similar misinterpretation of initial size-up factors also gave officers the wrong signal to initiate aggressive interior attacks that, in many cases, turned out to be fatal.
In the future, although firefighters must continue to consider the same traditional initial size-up factors when arriving at the scene of any structure fire, firefighters must remember that light, moderate or heavy smoke showing from an enclosed structure or space should be regarded as a sign of extreme danger.
Next: Enclosed-Structure Tactics and Guidelines
WILLIAM R. MORA retired as a captain after a 33-year career with the San Antonio, TX, Fire Department. He is a fire safety consultant concentrating in strategy and tactics and prevention of firefighter disorientation. He is the author of the United States Firefighter Disorientation Study 1979-2001 and Analysis of Structural Firefighter Fatality Database 2007. Mora can be reached at firstname.lastname@example.org.