On Feb. 27, 1997, at a third-alarm fire involving a thrift store, one of our firefighters was seriously injured after becoming disoriented when he became separated from his handline. Several other firefighters also became disoriented after encountering a pile of tangled handlines in the structure.
Two years later we thought we had a solution. I had returned from the Fire Department Instructors Conference with a Bernard Easy Exit Arrow, which is a directional arrow applied to firefighting hose. The arrow helps a firefighter safely exit a smoke-filled environment. Having taught classes in self-contained breathing apparatus and the search and rescue procedure, I knew the arrows would help us.
However, as I reviewed the safety report on the thrift store fire, I realized that the arrows would not have helped the injured firefighter because the nozzle he was using had been inadvertently jerked out of his hands during the fire. After losing the nozzle, he dropped to the floor and crawled around in circles unsuccessfully trying to locate the handline. At this time he was separated from his crew, and the evacuation tone was sounding. With conditions deteriorating he actually crawled deeper into the building thinking he was heading toward the exit but miraculously found and fell out of a window that had moments earlier been forced opened by a truck company.
This led me to try to determine what caused the disorientation and what could be done to prevent it. A three-year firefighter disorientation study was conducted. The study focused on 17 incidents in which disorientation played a part in 23 firefighter fatalities, as well as several injuries and narrow escapes occurring over a 22-year time span.
While carrying out standard operating procedures, firefighters today are making aggressive interior attacks into enclosed structures and extinguishing fires without becoming disoriented. This occurs simply because all of the requirements for disorientation are not present. During these fires, everyone managed to stay on the handline, the fire was near the entrance and was quickly extinguished, or prolonged zero visibility conditions never set in.
However, in the 17 occasions we examined through interviews andreports, the requirements were present and 23 firefighters lost their lives when aggressive interior attacks or primary searches were made. Firefighters must clearly understand the insidious nature of enclosed structure fires and must realize the next one they respond to may cause fatal disorientation.
An offensive strategy was used by the firefighters at every incident studied; yet because of disorientation, the outcomes were all unfavorable. In a representative disorientation scenario, companies would arrive to find light, moderate or heavy smoke showing from an enclosed structure. Following established SOPs, the companies would then make an aggressive interior attack to locate the seat of the fire or conduct a primary search. However, when companies couldn't find the fire or conditions deteriorated, some firefighters would be unable to evacuate.
The study found that firefighter fatalities are occurring nationwide at enclosed structure, basement and high-rise fires when aggressive interior attacks are made which result in disorientation. The study also determined that the potential for disorientation to occur did not depend on the construction, occupancy, size or age of the structure or whether the structure was or was not occupied, but rather on it's “enclosing or encapsulating” design.
In comparison to opened structures, the physical appearance of structures that caused firefighters to become lost were all distinctively different.
By learning to quickly identify these distinctive structures during size-up, the first-arriving officer will know if the structure has the potential to pose a serious disorientation hazard. If so, the officer can implement an SOP specifically designed to prevent disorientation and achieve a more favorable outcome.
The 17 structures in which firefighters became disoriented all had certain similarities in exterior or interior construction design. When considering structures with disorientation potential, there are five designs firefighters must be familiar with:
Opened structures have windows or doors of sufficient number and size to provide for prompt ventilation and emergency evacuation. During working fires at these structures and when possible, aggressive and effective interior attacks commonly are made.
Even though zero-visibility conditions may be encountered, ventilation efforts are effective in restoring firefighter visibility and orientation in about 15 minutes or less. Fire departments across the country safely and effectively manage these types of structure fires on a regular basis.
Opened structures with basements have windows or doors of sufficient number and size to provide for prompt ventilation and emergency evacuation. The description and appearance is almost identical to an opened structure; however, a basement window or basement door may be visible during an incident. In other instances, there may be no indication of a basement's existence.
In a documented NIOSH fire fatality report, Ohio firefighters making an aggressive interior attack into a basement at a single-family dwelling encountered light to moderate gray puffing smoke at the basement ceiling. An ensuing backdraft created by lifting a ceiling tile and introducing additional air caused the firefighters to become disoriented due to the blast of heat, loss of visibility and separation from the handline. Although there were two available means of egress, firefighters were unable to exit the basement due to the sudden increase of fire and smoke.
An associated hazard in this type of structure is the collapse hazard. In a recurring scenario, during an aggressive interior attack on the first floor of an opened structure with a basement, the weakened trusses below the floor supporting the unsuspecting firefighters collapses into the involved basement.
Enclosed structures have an absence of windows or doors of sufficient number and size to provide for prompt ventilation and emergency evacuation.
During working fires at these structures and while following established SOPs, aggressive interior attacks are being made in an attempt to locate and extinguish the seat of the fire. However, zero-visibility conditions become prolonged and ventilation efforts are very difficult, ineffective and at times unsuccessful.
Due to the loss of visibility, as well as other reasons including flashover and backdrafts, firefighters become separated from their handline during the interior attack or evacuation. As a result of disorientation and no readily available means of evacuation, firefighters are unable to exit the enclosed structure.
Enclosed structures with basements have an absence of windows or doors of sufficient number and size to provide for prompt ventilation and emergency evacuation.
There is double jeopardy associated with attacking this type of structure. In addition to the disorientation hazard as well as the flashover, backdraft and collapse hazard of the roof, there is an additional hazard of a flashover or backdraft in the basement or a collapse of the first floor into the basement.
In a well-documented NIOSH report, while searching for the seat of the fire in a tire service center Illinois firefighters observed black smoke covering the top third of ceiling space on grade level of an enclosed structure with a basement. Visibility then dropped to zero just prior to a backdraft that disoriented 10 firefighters and took the lives of two.
High-rise hallways in apartments, condominiums or hotels must be managed as enclosures with the potential for causing disorientation due to prolonged zero visibility, tangled handlines and disorientation secondary to flashover.
During working fires, high-rise hallways become hazardous enclosures within the structure. While advancing handlines in the hallway, firefighters will encounter locked and fire-rated solid doors, fire-rated walls, closed elevator doors, prolonged zero visibility, tangled handlines, and the intense heat of the fire. The only prompt means of egress will be the nearest stairwell.
If, during a fire, wind is blowing against the building on the same side as the room on fire and the window is open or breaks, entering wind will cause a flashover with blowtorch characteristics that will spread throughout the smoke-filled hallway. The flashover, which may occur instantaneously if the door is suddenly and fully opened, will travel to the nearest vent point. Because the charged handline connected to the standpipe in the stairwell is keeping the stairwell door partially opened, the flashover may travel to that stairwell.
Disabling nature of disorientation
The study showed that zero-visibility conditions cause firefighter disorientation in simple as well as complex structures. Without a handline as a guide, zero visibility will totally disable any firefighter.
Even familiarity with the floor plan may not keep the firefighter oriented in zero-visibility conditions. In a West Virginia incident two firefighters made entry to locate the seat of the fire at a grocery store by following the interior walls. After advancing to the rear portion of the store, both of the firefighters became disoriented when zero-visibility conditions set in. One of the firefighters was then unable to exit, even though he was a former employee of the store and knew the layout.
Several narrow escapes have also occurred at enclosed structure fires. In a Texas incident, a veteran district chief acting as an interior sector became so disoriented that he couldn't find his way out of a thrift store even though he was only 10 feet from the front door. Immediately after exiting, a flashover ensued. In incidents in Massachusetts, California, Texas and Arizona, many firefighters became disoriented to such a degree that while attempting to evacuate they found themselves tracing handlines back to the nozzle and seat of the fire.
Disorientation can occur easily and doesn't require the advance of handlines deep into a structure. The study showed that firefighters can become disoriented only 10 feet from the point of entry. The opposite is also true. In two overly aggressive attacks, advances were made over distances of 80 and 200 feet, resulting in disorientation.
No one is immune from disorientation. It strikes conscientious firefighters of all ages, ranks and levels of experience. However, the following formula of conditions must be present for disorientation to occur:
- Fire in an enclosed structure,
- Aggressive interior attack or search,
- Prolonged zero visibility, and
- Handline separation or tangled lines.
It's important to define the nature and duration of visibility that existed and caused firefighters to become disoriented. Unlike zero-visibility conditions found at commonly occurring opened structure fires, prolonged zero visibility is a heavy smoke condition that causes total and continuous loss of visibility for more than 15 minutes.
The onset of prolonged zero visibility will vary. Such conditions have been encountered on arrival, suddenly after arrival and as long as 52 minutes after arrival. This is significantly more hazardous at enclosed structures because firefighters can't become reoriented.
The unfamiliar environment, along with deteriorating conditions, low air supply and disorientation, often causes panic and calls for mayday in the structure, as well as unsafe independent action from firefighters outside the structure desperately attempting to locate a lost firefighter. On many occasions, control of the incident during this time frame was lost.
In terms of air supply, a 15-minute time span is important to the firefighter making an aggressive interior attack because it's the approximate time a 30-minute — rated air tank will supply a working firefighter.
Safety will be compromised when a firefighter is unable to reach an exit within five minutes after a low-air warning. The study found many firefighters running out of air before completely exiting the structure. Although firefighters walked into the structure at the start of the incident, several needed to crawl out from the seat of the fire or the deepest point advanced.
While evacuating in prolonged zero visibility, firefighters also encountered extreme heat, scattered contents and debris, and hazards that caused separation from handlines, including:
- Loss of balance or footing.
- Collision with firefighters or unseen objects.
- Entanglement in wires from air-conditioning ducts.
- Exposure to falling contents, sheet rock or other building materials.
- Drop through floor into basement.
- Exposure to flashover or backdraft.
Prompt evacuation also was affected by the formation of fireground spaghetti. During an interior attack firefighters will instinctively advance enough additional hose to be able to reach the deeper portions of the structure. However, loops of hose can form and cause confusion when evacuation is necessary. In 10 of the 17 incidents examined, firefighters encountered tangled hose and, in some cases, required assistance from rapid intervention teams.
Shift to prevention
To prevent a firefighter from ever becoming disoriented in the first place, we must change our operational methods for enclosed structures.
Fire departments may reduce the risk of disorientation by learning to identify hazardous enclosed structures, obtaining safety equipment and conducting disorientation prevention training. Training should include information based on the study results.
Firefighters must understand that fires involving any type of enclosed structures present a much greater disorientation hazard than opened structures and must be identified early in the incident. If you aren't certain if the structure fits the description of an enclosed structure, play it safe and consider it one. For example, structures that have windows with security bars must be treated as enclosed structures because rapid evacuation won't be possible.
Enclosed structure fires have been taking the lives of and seriously injuring firefighters for decades. To safely confront these high-risk hazards, three-in/three-out minimum staffing is recommended at the outset. The interior assessment crew and RIT each consists of a nozzle operator, an officer with camera, and a third firefighter to help advance the line.
Of course, reliable portable radios are a must to ensure that firefighters are alerted to the existence of a basement, the need to use the enclosed structure SOP or the change to a defensive attack. The radios must allow firefighters to hear an order to evacuate over any fireground noise.
Elements of safety
There are four major safety elements that can prevent disorientation: standard operating procedures, thermal-imaging cameras, safety directional arrows and a rapid intervention team.
- Standard operating procedure
Due to serious hazards associated with fighting an enclosed structure fire, an aggressive interior attack to find the seat of the fire should not be implemented at the beginning of the operation. Instead, an enclosed structure SOP, using a cautious interior assessment at the outset, should be used. (See sidebar below.)
- Thermal-imaging camera
When light, moderate or heavy smoke conditions are found on arrival, thermal imagers may allow firefighters to assess structural integrity of truss floors, roofs and walls. They also can reveal fire conditions, pinpoint the seat of the fire, determine if a basement is involved and help re-orient those firefighters who become separated from their handline.
- Safety directional arrows
All attack lines, including high-rise packs, should be equipped with a system of directional arrows that help firefighters with gloved hands to safely exit structures in zero-visibility conditions in the shortest possible time.
Hoselines often are the cause of serious mistakes during evacuation, but directional arrows prevent firefighters from:
- Following handline back to nozzle.
- Becoming confused by spaghetti.
- Following a separate handline back into a different part of the building.
Training in the use of directional arrows should include maintaining company integrity, verbal communication and physical contact during company evacuations. Single firefighter evacuation because of crew separation also must be learned. Evacuating firefighters should not retrieve advanced hoses during prolonged zero visibility, as they may be used as lifelines by other firefighters exiting the structure.
- Rapid intervention team
During an interior assessment, use of an RIT equipped with a charged handline, established water supply and thermal imager provides immediate availability of another fire fighting stream and of a back up camera should the first become inoperable. The camera equipped RIT represents the fourth element of safety that attempts to prevent disorientation.
Firefighter fatalities, injuries and narrow escapes caused by disorientation are continuing to occur across the nation.
If casualties are to be reduced, firefighters must receive information pertaining to the different types of enclosed structures and their hazards. Acquisition of safety equipment that prevents disorientation also will be required, as will training in company responsibilities when executing an enclosed structure SOP.
When every first-arriving officer is trained to determine that an enclosed structure is on fire and subsequently orders implementation of an enclosed structure SOP, the fire service will take the first step in preventing cries of mayday.
William Mora is a captain with the San Antonio Fire Department.
The disorientation fires
These are structure fires in which disorientation occurred following an aggressive interior attack. Some additional data is also provided.
Texas, 1979, enclosed structure with basement
This auditorium basement fire, which occurred after business hours, had prolonged zero visibility on arrival that then lasted seven hours. The building had a masonry exterior with narrow casement windows, many of which had security bars. The structure was extinguished defensively.
Texas, 1985, enclosed structure with basement
The 4-story office building was used as a dental office. The fire in the basement occurred after business hours and nothing was showing on arrival. Prolonged zero-visibility conditions were encountered after entry and lasted 45 minutes. Firefighters were exposed to a rollover and confused by a tangled handline as they attempted to evacuate. The building had a brick-and-masonry exterior with one window in the front and a single swinging door in the front and rear. The foyer where firefighters were lost measured 30 feet deep by 60 feet wide.
Massachusetts, 1987, enclosed structure with basement
This dye-processing warehouse, which was occupied at the time of the fire, produced prolonged zero visibility after arrival. Firefighters encountered tangled handlines as they evacuated the 3-story structure. The structure had a masonry exterior in which cinder blocks were used to seal pre-existing windows. It also had one roll-up door and two single swinging doors on the side of the building nearest the fire.
Texas, 1997, enclosed structure
This thrift store was originally a theater. Prolonged zero-visibility conditions were present on arrival and lasted one hour. Firefighters were exposed to a flashover and encountered tangled handlines near the main entrance. The building had concrete block enclosing about 80% of the building's exterior surface, with plywood and gypsum board covering some of the few windows. Disorientation occurred 30 to 35 feet in the building, and the fire ultimately was extinguished defensively.
California, 1998, enclosed structure
The commercial structure fire occurred after business hours with prolonged zero-visibility conditions developing after arrival. Firefighters encountered tangled handlines as they attempted to evacuate the structure. The building had a masonry exterior and measured 110 feet in length and 59 feet in width. Disorientation occurred after crews advanced about 40 feet into the structure. The fire was extinguished defensively.
Ohio, 1998, open structure with basement
This single-family dwelling had no occupants home at the time of the basement fire. Light smoke was showing on arrival, but prolonged zero-visibility conditions occurred suddenly following a backdraft that exposed firefighters attacking in the basement. The home had a hardboard siding exterior and measured 28 feet wide by 50 feet long. Disorientation occurred about 25 feet into the basement, and the fire was extinguished defensively.
Illinois, 1998, enclosed structure with basement
This commercial tire service center sustained a fire in the rear storeroom. The fire, which occurred after business hours, had light haze showing initially in the sales area. Prolonged zero visibility occurred following a backdraft in the storeroom that exposed 10 firefighters. Tangled handlines were encountered as they attempted to evacuate. The structure, which had a masonry block exterior and glass front, measured 150 feet wide by and 62 feet deep. Disorientation occurred after advancing up to 20 feet into the enclosed service area, and the fire was extinguished defensively.
North Carolina, 1998, enclosed structure
The auto salvage storage building fire occurred after business hours. Prolonged zero visibility occurred after a flashover exposed two firefighters. The firefighters also were confused by the tangled handlines that had formed inside the building. Disorientation occurred after advancing about 80 feet into the structure, which had a corrugated metal exterior. The structure finally was extinguished defensively.
West Virginia, 1998, enclosed structure
This grocery store, which was occupied at the time of the fire, initially had heavy black smoke emitting from the ventilation system at the rear of the structure, with good visibility and light smoke about 1 foot thick across the ceiling. Prolonged zero-visibility conditions occurred after arrival. The store had a masonry-and-brick exterior with six small windows along the front of the store, which measured 120 feet wide by 180 feet long. Disorientation occurred after advancing 80 feet into the structure. The fire was extinguished defensively.
Massachusetts, 1999, enclosed structure with basement
This 6-story cold storage warehouse had light to moderate smoke showing initially but produced prolonged zero visibility after arrival. The vacant structure had 18-inch-thick exterior brick walls designed to enclose approximately 90% to 95% of the structure. Six windows were present but were covered with plywood. Disorientation occurred deep in the structure. The fire was extinguished defensively.
District of Columbia, 1999, enclosed structure with basement
This 2-story townhouse unit, which measured 19 feet wide and 33 feet long, had no occupants at home at the time of a basement fire. The structure had a brick exterior and windows with security bars. Prolonged zero visibility occurred after arrival, and firefighters were exposed to a flashover. Disorientation occurred about 20 feet from the front door. The fire was extinguished defensively.
Missouri, 1999, enclosed structure
The paper warehouse fire occurred during business hours with light smoke showing on arrival. Prolonged zero-visibility conditions occurred 52 minutes after arrival. The exterior was constructed of metal, rubber and stone particulate and measured 500 feet wide, 600 feet long and 25 feet high. Many firefighters became disoriented in the tangled handlines that formed in the interior. Disorientation occurred both near the exit and 200 feet into the building.
Texas, 2001, enclosed hallway
The fire in this occupied high-rise apartment building was on the fifth floor. Prolonged zero visibility occurred after arrival. Firefighters were exposed to blowtorch flashover and encountered tangled handlines as they attempted to exit. There were winds of 16-to 39 knots during the fire, which was extinguished defensively.
Arizona, 2001, enclosed structure
This grocery store was occupied at the time of the fire and initially had heavy smoke showing at the rear of the store, with light smoke showing in the store interior. There were then prolonged zero-visibility conditions during the incident, and firefighters were exposed to flashover. Disorientation occurred deep in the structure. The exterior of the building was of concrete cinder block with plywood partially covering windows at the front. The fire was extinguished defensively.
SOPs for enclosed structures reveal interior attack options
An enclosed structure standard operating procedure must prevent disorientation by eliminating the hazards encountered during enclosed structure fires.
While the SOP should provide command officers the flexibility needed to achieve the best possible outcome, it should include, at minimum:
- The use of an incident command system.
- Early recognition and identification of hazardous enclosed structures.
- Establishment of ventilation sector.
- A cautious interior assessment at the outset to determine if it's safe to make an interior attack.
- Use of a combination timekeeper/accountability sector to guard against exceeding the air supply and to maintain accountability.
- Use of a combination rapid-intervention team with thermal-imaging camera, charged handline and established water supply.
- Establishment of targeted areas for primary searches, which are within the limitations of PPE.
- Recognition of exterior and interior backdraft conditions and subsequent ordering of appropriate ventilation.
- Recognition of pre-flashover conditions.
When command follows the basic SOPs for enclosed structures, several attack options will present themselves.
A cautious interior assessment involves looking into the structure with a thermal-imaging camera to assess conditions and locate the seat of the fire to determine if an offensive attack, short interior attack or defensive attack will be made. It's used in place of the traditional fast and aggressive interior attack.
An offensive interior attack may involve advancing, in zero visibility, into structures with hazardous arrangements or contents or across expansive floor areas from the unburned side. An interior attack from the unburned side, which is a widely used strategy, has proved to be safe and effective for use in opened structures.
However, when distances in enclosed structures are excessive, arrangement or amount of contents hazardous, and life safety is not an issue, it may be safer to initiate a short interior attack, even if breaching is required. A short interior attack involves advancing handlines to the seat of the fire over the shortest possible distance from the exterior.
Used for enclosed structures, this type of attack may increase safety by maximizing the efficiency of air supply; preventing handline separation and disorientation; and avoiding exposure to flashover, backdraft or collapse. The short interior attack uses existing doors or windows to advance handlines, but it also may involve forcible entry by truck companies or technical rescue teams to breach exterior or interior adjoining walls, creating access points close to the seat of the fire.
When such an attack isn't safe or possible to accomplish in a timely manner, a defensive attack is implemented. It should be noted that in 12 of the 17 incidents examined in this study, the fire was ultimately extinguished defensively following firefighter fatalities, injuries and narrow escapes.