“Webster Parish Fire District 3, respond to a reported structure fire at 33 Lake Ridge Road. Caller reports that a large garage and workshop on the back of the property are on fire. We are dispatching your automatic-aid tankers as well.”
For many suburban and rural fire departments, this page out is a common occurrence in my area of northwest Louisiana. In Bossier and Webster parishes, an increasing number of property owners are building large garages, sheds, workshops, and other residential outbuildings. To some, these fires may seem simple, but these buildings pose construction, contents, and often water supply challenges for many short-staffed combination and volunteer departments.
As a training officer for two all-volunteer rural fire districts, it is my responsibility to develop relevant training and response policies. Over the past several years, I have witnessed these structures evolve from buildings housing small workshops or a myriad of stored or discarded household materials into larger at-home commercial workshops; garages housing large recreational vehicles, campers, and boats; small businesses housing commercial mowers, fuels, and lubricants; and vehicle repair and auto body businesses.
Construction, Contents, and Fire Behavior
In many rural farming areas, these buildings are likely still used for more traditional agricultural purposes such as hay, feed, and farm equipment storage and as shelter for horses, cows, and other animals. However, in many areas they are now used for other purposes. Although “traditional” outbuilding fires can be extremely challenging, most departments are well-versed in the buildings’ construction, the burning characteristics of the fuels involved, and the required fire suppression and water supply operations.
(1) Crews responding to this residential outbuilding fire in my combination district found heavy fire conditions but achieved rapid knockdown. The fire originated on the exterior, caused by a mower leaking fuel. (Photos by author.)
(2) Career and volunteer personnel responding to this residential shop fire with two engines and a rescue company in my combination district found heavy fire conditions venting through the roof and an open garage door on arrival. They deployed a 2½-inch line and controlled the fire within two minutes.
As the change from natural legacy fire fuels to modern hydrocarbon-based fire fuels has affected the fire behavior firefighters experience in home and commercial business fires, a similar change has occurred in residential outbuilding fires. The hydrocarbon-based fuels present in these structures are now creating hotter and faster-burning fires than we used to see. Departments in farming areas still see hay-fed fires in these structures, but the fires that many departments now respond to have changed according to the building’s use and the fire fuels present. Fire departments must identify the contents found in these structures within their districts and adapt their operational tactics to meet the threat resulting from the change in occupancy and fire fuels.
Commonly, these structures may contain large recreational vehicles (RVs), large towable campers, multiple antique vehicles, short-track and dirt racing cars, and boats of various sizes. If race cars are present, these buildings may also contain drums of regular and high-octane fuels and multiple sets of spare tires. A fire involving these items is challenging enough when it is burning out in the open; but, when it is inside a structure, the operation becomes more complex and much more dangerous for firefighters. Even one burning golf cart or all-terrain vehicle can create a significant amount of dense, toxic smoke.
If the structure houses an at-home car repair and auto body service, large amounts of paint strippers, paints, and flammable resin body compounds will be present. Depending on the usage, these structures may contain pressurized gas cylinders (e.g., propane used for grills and RVs or welding gases). It is critical that the incident commander (IC) identify these hazards and conduct a thorough risk evaluation before committing members to interior operations when such conditions are present. The quantity of the materials present may require Class B foam operations. The IC must ensure that a sufficient quantity of foam concentrate is on scene to suppress the fire completely before beginning application operations.
If the storage area is significant, you may find hoarder conditions that will challenge firefighters’ movement through the structure and present entrapment dangers should the stacks of materials collapse. These conditions can also result in rapid and possibly violent changes in the fire’s behavior and its rate of spread because of the large amount of combustibles. Once again, the IC should identify these conditions as soon as possible after arrival and implement a plan to reduce, when possible, the dangers of these conditions to the members. If the IC determines that interior operations are too hazardous, he should switch to defensive operations.
These buildings are often constructed of lightweight materials, commonly nondimensional lightweight lumber, often trusses. These present very little resistance to fire and will quickly weaken and burn away, with a high probability of early structural collapse. In some cases, some use modern engineered lumber, such as oriented strand board I-beams, that will also burn quite easily and may fail very early in the fire, especially when exposed to the heat produced by hydrocarbon-based materials featured in recreational vehicles, boats, and cars. Firefighters must take every opportunity to note how these buildings are constructed while they are being erected. A few minutes of windshield preplanning may save firefighters’ lives.
Even when the building’s structural members are constructed of steel, generally it’s a lightweight truss design, which, though somewhat more resistant to the effects of fire compared to wood, will nevertheless elongate and deform when exposed to temperatures of more than 1,000°F, which will likely result in structural failure. Again, the fire department must understand the construction of these structures in their response area.
As an example, we are still seeing a fair amount of these buildings being constructed with medium or heavy purlins, which are steel beams that are much heavier than lightweight trusses and, as such, have a fair amount of resistance to fire. A building that uses purlins may give the members additional time to operate in the structure before a structural collapse. This information can likely be obtained by contacting the dealers of these types of structures as well as local contractors and builders.
Additional challenges of these structures are their locations in the fire district and their locations on the property. These buildings tend to be on larger residential properties that have the space to accommodate them. Because of their rural/semirural locations, delayed fire department notification and extended response time may occur, resulting in advanced fire conditions on arrival. Prepare for those conditions and be ready to implement a transitional fire attack.
In some cases, these buildings will be near the residence close to the road, but they also may be set deep into the property, sometimes on rough or uneven dirt roads or paths well off the paved road. This will prove challenging for larger vehicles such as engine and truck company apparatus and tankers. In some cases, only smaller units (e.g., midi or mini pumpers) or, in difficult road conditions involving mud or snow, four-wheel drive brush apparatus will be able to access the structure. In these cases, fire operations may be forced to operate with a very limited water supply unless a large-diameter supply line can be laid into the fire area. This situation may require the IC to make difficult decisions such as whether to protect the exposures, extinguish the brush fires started by the structure fire, or apply water to the burning structure itself.
As with any fire response, you must evaluate the staffing level available at various times of the day; it will drive the tactics you use at the fire. Evaluating the staff response is key in preplanning, requiring honesty in self-evaluation by the department leadership.
For these types of fires, the minimum level of initial staffing should be no fewer than 18 members plus apparatus drivers/pump operators. This will give the IC adequate resources for two three-member attack line teams, a four-member truck operations crew for forcible entry and ventilation, a three-person incident command staff, and a four- or five-member rapid intervention team (RIT). Larger structures identified in preplanning may require a larger initial response.
It is quite possible that an all-volunteer department may have an excellent response of 20 to 25 members during the evening hours and weekends but only five to seven responding members during the day. The same situation may exist with volunteers supplementing career members in a combination department. If this is the case, or if personnel in general are lacking, the department should arrange for automatic mutual aid on the initial response. In some areas, automatic mutual aid is an everyday occurrence. Such was the case with my previous volunteer department in northern Vermont; a structural incident would have three or four departments dispatched on the initial alarm. Other areas are still reluctant to use automatic aid, even though staffing may be an issue. It often comes down to pride and the stigma some members associate with needing help in their response area.
Also critical is that the department look at what duties the responding members can perform. As an example, a volunteer department may respond with 15 to 20 members but, as a primarily older organization, it can only respond three to five interior/self-contained breathing apparatus qualified members. In such cases, the responding department should consider using automatic mutual aid to provide the IC with enough qualified interior personnel to properly and safely staff the fire attack and RIT.
If the department determines that the number of officers available will be inadequate to both supervise fire crews and perform incident command functions, it should consider dispatching additional chief officers from mutual-aid departments.
How do you conduct an effective fire attack when responding to a working incident in these structures? Four simple words: Big fire, big water. Although it is not a new idea and has been much discussed in the fire service over the past few years, this concept is even more critical when you are operating in today’s residential sheds, garages, and outbuildings . It is even more important considering that you will often find these structures in areas with somewhat more extended response times and, consequently, more advanced fire conditions on arrival. Although in some cases an offensive interior attack may be possible initially using 13⁄4-, two-, or 21⁄2-inch handlines, these fires will often require some exterior softening operations before entry.
In most cases, a transitional fire attack will likely be the most effective tactic. Begin with an exterior fire attack designed to soften up fire conditions before making an interior attack. This may prove useful when the number of initially arriving or interior-qualified personnel is very limited or inadequate.
One valuable tool for softening is the apparatus master stream or a single-inlet ground monitor supplied by a 21⁄2- or three-inch supply line. With a given flow rate of at least 300 gallons per minute (gpm) for the single-inlet monitor or 400 to 500 gpm for the master stream, you may achieve considerable fire knockdown within 20 to 30 seconds. These devices will provide excellent flow rates; significant reach from the exterior; and a stream that will penetrate deep into the structure, especially if using a smooth bore nozzle.
(3) This large residential outbuilding has no exterior indications of its use, contents, or fire load. It’s critical that members understand that such structures could contain a benign or an extremely volatile fire load and be prepared to encounter a variety of fire conditions. Prepare for the worst-case scenario and respond with sufficient apparatus; personnel; and, in rural areas, water.
Members must also examine the grade outside an outbuilding; it will most likely slope down and burning liquids will flow toward outside personnel operating at a doorway. To avoid a running spill fire and shrapnel from exploding containers, direct the streams from flanking positions, not directly in front of a doorway.
This is important since water consumption is one of the major concerns in using high-flow devices in a rural environment. Knockdown may require as little as 100 to 200 gallons of water if the device placement is solid and the water is directed at the correct location. In some cases, apparatus placement may not allow the use of an apparatus-mounted master stream. For example, if the apparatus is too close to the structure, you may be unable to angle the master stream low enough to flow through a building opening such as a garage door. This requires training and understanding how the big initial hit is critical for a successful transitional fire attack.
You can achieve exterior softening using a 21⁄2-inch line (preferably preconnected), especially when the nozzle is a smooth bore that can flow more than 275 gpm. Although a 11⁄16-inch tip at 50 pounds per square inch (psi) can flow about 240 gpm, achieving a higher flow of at least 260 to 270 gpm will require a 11⁄8-inch or 13⁄16-inch tip. You can easily achieve this flow with one member operating on the 21⁄2-inch line. Again, this exterior application can significantly darken down the fire using a flow as little as 100 gpm from the booster tank of the initial-arriving apparatus. If the apparatus has a Class A foam proportioned system, the flow to knock down the main body of fire may be even less. Training on the various one-member hose handling techniques may be required if a department does not often use 2½-inch lines in an aggressive/offensive mode.
When operating with limited staffing and expecting a single member to deploy the line, it is important that the preconnect not exceed 100 feet in length. If it does, the single member will have difficulty in deploying and placing the line in service within a target time of 90 seconds. This will enable you to darken down the fire with minimal staffing since you need only one member to operate a truck-mounted master stream and, at most, two members to set up a single-inlet monitor or deploy and operate a 21⁄2-inch handline equipped with a smooth bore nozzle at 50 psi.
Once you have knocked down the fire using the initial exterior master stream device, single-inlet monitor, or 21⁄2-inch handline, assuming the building is still structurally stable, you can begin an interior attack. You should staff this line with enough members to allow rapid and effective advance through the structure. In addition, equip the officer or senior crew member with a thermal imaging camera (TIC) to evaluate fire conditions before and as the crew advances into the fire building. Once fire has been knocked down with a 21⁄2-inch line, you can wye the line and employ two 13⁄4-inch handlines to complete extinguishment.
Just as important as the initial exterior line selection is the interior attack line’s flow rate. I advise considering a minimum flow of at least 150 gpm for today’s modern fuels. You can achieve this using a 7⁄8-inch smooth bore tip (approximately 160 gpm) or a 15⁄16-inch tip (180 to 190 gpm) on a 1¾-inch line. You may also obtain the flow through a 150- or 175-gpm fixed gallonage nozzle on a 13⁄4-inch handline. In both of my volunteer departments, we have been using low-pressure 50-psi/150-gpm combination nozzles as well as smooth bores for the past three to four years and have found them to be quite effective in minimum staffing situations. The two-inch handline will also easily provide a flow in excess of 200 gpm and will be very effective. No matter the nozzle choice, remember that a minimum flow of 150 gpm must be achieved for effective and, more importantly, safe interior fire attack.
(4) In a neighboring fire district, this building includes an apartment, a garage, and an open meeting space capable of holding up to 150 people. It’s critical that the responding department or fire district understands the building’s multiple uses and has an accurate, up-to-date preplan to make solid strategic and tactical decisions.
ALSO BY ROBERT CALLAHAN
Initially, position and flow the interior attack line to extinguish any remaining fire or cool the steel in the structural members from the entry point identified using the TIC. Then use the TIC to reevaluate the structural members’ condition and determine the safety of interior operations in the building. If there is any doubt about the structure’s stability, limit fire attack operations to exterior operations, including overhaul. If you decide to advance, use the TIC to identify the hottest areas of burning, monitor the overhead heat conditions, and continually reevaluate the overhead structural members. Additionally, use a gas detector to ensure that personnel are not standing in runoff contaminated with fuel or leaking liquefied petroleum gas that could reflash suddenly and without warning. Accordingly, if you have enough personnel to do so, assign firefighters to cover firefighters conducting overhaul with large dry chemical fire extinguishers.
It will likely require more than one interior line, especially if the structure contains large vehicles such as RVs or multiple smaller vehicles. Assigning each line to a specific work area will eliminate the possibility of hitting other crews with opposing streams in the large open areas found in these structures. Assign an officer to direct interior operations to prevent issues such as members being hit by opposing fire streams.
As discussed earlier in the article, the size and contents of these buildings may require significant water supplies for fire suppression. Often, these buildings are found in areas not covered by a hydrant system.
Where there is a well-supplied hydrant system, providing adequate water may just require laying a large-diameter supply line into the incident. For areas without this capability, it is critical that the responding departments understand their ability to deliver the required fire flow using tankers/tenders. Firefighting operations at these structures require a minimum sustained flow of at least 500 gpm, which will supply a master stream device, two 21⁄2-inch handlines, or three 1¾-inch handlines. In larger structures, the minimum flow should be 750 gpm, especially if an exterior operation requires heavy streams.
If the responding department cannot sustain that flow with its own tankers/tenders, strongly consider automatic or an early mutual-aid request for additional tanker/tender support. If the department does not usually use tanker shuttle operations, develop and implement training evaluating the number of tankers required, establishing tanker/tender fill sites, drafting out of portable ponds, and water shuttle apparatus flow patterns. Planning and training are especially important in departments with limited experience in tanker/tender operations.
When the only access to the fire building is by a long, narrow driveway, consider having the first- or second-arriving engine lay a supply line from the road entrance to the driveway so that tankers/tenders can perform water shuttle operations on the road to avoid having to maneuver in and out of the driveway. If an engine is not available to pump the line, consider the use of a clappered siamese, which will allow one tanker to hook up while the second is pumping the supply line. This will allow for a very smooth transition when the first tanker runs dry.
Establishing the RIT before interior fire attack operations begin is also critical. In some areas, the staffing available to establish these teams may be a challenge, but it is a firefighter safety priority. Consider a three-member RIT as the minimum; four or five would be ideal. Significant research has demonstrated that in most nonresidential fire conditions, locating and removing a down member will require more than two or three personnel. Although RIT members may be tasked with exterior softening operations such as forcing doors, they must be available at a moment’s notice to perform their primary assigned duty of rapid intervention. Members assigned to the RIT should be trained in conducting effective search operations, wall-breaching operations for all building construction types found within the district, and firefighter packaging/removal techniques.
Incident Command System
Finally, consider the role of the incident command system (ICS) in managing the fire. Again, in some areas, having enough officers and members to develop an expanded ICS will be a challenge; in the long run, the benefits of a properly managed and well-supervised scene will far outweigh the staffing costs. The IC should not attempt to manage all the aspects of the fire alone but implement an expanded ICS as soon as possible into the incident. It should, at a minimum, be an operations chief, a safety officer, a water supply officer, and a staging officer. In addition, assign an officer to supervise interior fire operations, an aide to assist the IC, and possibly a communications position to assist the IC with managing radio traffic. With larger buildings, assign sector officers to manage operations on multiple sides of the structure.
Specific training for these operations will result in a smoother running incident, especially with residential outbuilding incidents. Adapt the following residential/commercial fire skills training specifically to the needs of these incidents: size-up and initial radio reports; building construction; outbuilding response operations; transitional fire attack using master streams, 21⁄2-inch handlines, and single-inlet monitors; hoarder home interior fire attack operations; tanker/tender operations; and an expanded ICS.
The training should include a classroom lecture, whiteboard exercises, and field work relevant to these structures. If your response includes mutual aid, all responding departments should train together so at a fire everybody will be operating on the same page.
. . .
With the changes in building construction, occupancy, and contents, fire operations at residential outbuildings have become more complex and staffing intensive. The fire department command staff must identify these buildings in their district and develop response plans for them. These plans may include provisions for additional staffing and apparatus on the initial alarm, primary and supplemental water supply operations using tankers/tenders, and additional command officers. Training officers must identify and address the training needs and have automatic- and mutual-aid partners train with them.
ROBERT CALLAHAN has been in the fire service for almost 40 years. He is the fire prevention officer and a captain with Bossier Parish (LA) Fire District 1 and the training officer and a captain with Webster Parish (LA) Fire District 7. He is the training chief and former assistant chief with Webster Parish (LA) Fire District 3. He is an adjunct instructor with the Louisiana State University Fire Training Institute, a contract instructor with the National Fire Academy, and a district representative for the Firefighter Cancer Support Network. He has instructed at conferences throughout Louisiana, including at the Louisiana Arson and Fire Prevention Association Conference, the LSU-FETI Officer Conference, the LSU- FETI Municipal School, the Louisiana Fire Chiefs Association Annual Conference, and the F.O.O.L.S. Brothers of the Boot events.