Warehouse Size Structure Fires

I recently viewed a video of a warehouse fire that reminded me of how frequently I see fire departments applying residential structure fire tactics to warehouse size fires. I often wonder what the root cause of operating this way is. Is it due to a lack of knowledge, improper training, lack of preplanning and underestimating the resources required, department culture, complacency, habitual operations of doing the same thing for every fire call, or simply a failure to match the appropriate tactics for the call you’re on? Every fire incident is different and requires an effective and ongoing size up, situational awareness, and a full 360 degree view of the incident scene to fully understand conditions and to match those conditions with appropriate tactics.

Warehouse size structures are often commercial structures that require big water from the start due to the increased square footage, open space floor plans (equals more air for fire), high ceilings, and the increased fire loading. However, today we have single family dwellings (includes McMansions and mansions that are in excess of 5,000 square feet. These structures often have open floor plans with less compartmentation, cathedral ceilings, synthetic contents, energy efficiency, and are constructed of light weight wood materials. Even though they are considered residential occupancies they resemble a commercial size structure with similar challenges. Tactical changes are necessary to deal with this size structure verses a rambler. It may be necessary to begin fire operations with a 2 ½” line or larger appliance rather than the traditional bread and butter 1 ½” – 1 ¾” handline.

Effectively dealing with warehouse size structures, whether commercial or residential, begins with initial preplanning of these structures and establishing SOPs for handling such buildings. Over the years, the Fire Departments of Northern Virginia, made up of 14 separate fire department agencies, have successfully created joint operating guidelines (SOPs) in which all 14 departments operate from. This creates seamless operations based on dispatch order, and has proven its value consistently during standard and mutual aid responses.

Preplanning should include identification of current and new warehouse size construction within each jurisdiction that poses potential fire challenges. This information should be documented and communicated throughout the department and to mutual aid jurisdictions that may be subject to responding to these structures. Multi-company building familiarization and training should be emphasized and should include the appropriate mutual aid companies.

In many cases, the 1 ¾” handline can handle the bulk of residential structure fires, but when the square footage of structures increases significantly, whether commercial or residential, firefighters must consider the 2 ½” line or larger caliber streams depending on existing and potential conditions. Some would argue a lot of fire can be extinguished with a 1 ¾” handline, but we are not in competition to debate this on the fire ground. Anticipate big fire potential in large structures and begin with the appropriate size line for the fire.

Within the NOVA Fire Departments, the minimum size line for any commercial structure is a 2 ½” handline. This could include a warehouse building, commercial high rise, and in the residential setting, McMansion or larger single family dwelling occupancies. The larger line is an appropriate match for a larger anticipated fire situation. Higher water volume can have an immediate impact on lowering temperatures, extinguishing fire, can aid in preventing trigger events, offers better reach and deeper penetration, and when things are going south, can often offer sufficient protection to clear personnel from the immediate hazard zones.

Our understanding of modern fire dynamics can be applied to warehouse size structures. We often begin with reading the smoke volume, velocity, density, and color to narrow down the location of the seat of fire and the extent of fire. Warehouse size structures often have high ceilings that will hold a substantial amount of heat and smoke (unburned fuel). Firefighters must recognize this as these conditions may not be as easily observed at ground level or observed at all if tunnel vision is influencing our senses and situational awareness. Warehouse size structures can be prone to early collapse potential due to unprotected steel and light weight structural elements. Getting ahead of fire with fast, sufficient water will be essential to controlling fire during an offensive attack mode, and even more essential should the strategy change to a defensive mode.

Warehouse size fires can lead to other complicating factors such as rapid fire spread in the open spaces, fire extension to exposures, secondary self-sustaining metal deck roof fires, initial staffing and resources becoming overwhelmed, etc. Part of the preplanning should include the potential complicating factors, which should be anticipated.

The preplanning should include an evaluation of construction type, materials stored within warehouse size structures, access points and forcible entry needs, utilities, availability of fire protection systems (sprinklers or other fire suppression systems) or lack thereof, as well as the available flow rate and location of hydrants. The latter is significant in the event apparatus and personnel are required to function outside of collapse zones.

With respect to available sprinkler systems, if the structure is equipped with a sprinkler system, stretching lines to and supplying the system should be a priority, as this can often get water on the fire faster. Even if the system is damaged due to fire, it may still be the fastest method to get water to the seat of fire.

Warehouse size structure fires require a full on assault on fire with high volume water hitting the seat of fire and cooling wall and ceiling area surfaces. There is no time to waste and very little time available to execute an offensive attack. Warehouse size fires can be so challenging to firefighters the odds appear against firefighters from the start, so every action has to count. Otherwise, you’ll quickly find yourselves in a defensive posture, which may be the best option upon arrival depending on conditions and extent of fire.

Ventilation in a warehouse size fire is no different than ventilation in any size structure. Any openings in the structure provide ventilation, which in turn can create air intakes, exhaust points, and establish flow paths. Ventilation, or air, without first controlling the fire with sufficient water will increase fire intensity and will rapidly spread fire, and could create trigger events like flashover or backdraft.

If the structure is closed up and smoke is puffing, it’s a clear indication the fire is ventilation limited. It’s choking down and is too rich to burn without air. This condition can work in favor of firefighters by allowing them to apply water into the compartment from small openings in order to attack fire and cool the environment. As conditions change for the better, apply limited and cautious ventilation to maintain the rich environment. Alternatively, opening up bay doors and ventilating the roof will provide air to the ventilation limited fire and cause the smoke to light off or could trigger a violent backdraft.

When no life safety issues are present and advanced fire conditions are beyond immediate control, it may be necessary to ventilate the building in order to open it up and allow the energy to release and fire to show itself, and then address the fire in a defensive posture. This is not ideal, but in some situations may offer a better option. Ensure adequate water supplies and large caliber appliances are supplied and in position in advance of releasing the energy. Its best to keep the structure as closed up as possible, until resources are in position and ready to surround and drown.

The use of thermal imaging cameras should be employed to identify known location trapped occupants, to identify the seat and extent of fire, to observe heat signatures, to observe structural instability of unprotected steel components, and to aid in maintaining orientation under smoke conditions and situational awareness.

Warehouse size structure fires are challenging to say the least. This article doesn’t address every circumstance, but should offer you something to consider as you anticipate your own warehouse size structures, the fire potential, and the minimum resources required to effectively mitigate. Proactive preplanning, building familiarization, establishment of effective SOPs, ongoing training, which should include multi-company and mutual aid partners, and other preparations are necessary to identify existing and new construction warehouse size buildings in your response area and to predict the fire challenges and how to prevent them, or at least effectively deal with them when they occur.

As an aside, I’d like to bring attention to the learning opportunities video footage of structure fires offers firefighters. Everywhere we go there is a cell phone or other device recording video of fires and fire ground operations in real time. Technology brings this footage to us instantly in many cases. It gets posted to a host of social media outlets, which makes it easy to speculate or judge without proper context and facts.

As you review video footage, it should be from a place of learning, not a place to judge or to be critical of brother and sister firefighters, who in most cases are doing their best with what they’ve got. No fire department or firefighter is perfect and there is always room for improvement. Use the videos as a learning opportunity to learn from others and to improve on your knowledge, training, and operations.

It’s interesting how firefighters often focus on things done wrong or complacent behavior when viewing video footage. Sometimes this overshadows the things being done right. No need to call out the negatives, because it’s often obvious to every firefighter and this is not where your focus should be. Instead, focus on how what you saw will influence you to be better and to do your job better. Review the video as if it were your fire incident, your crews, and determine what your actions would be based on your assignment, your training, your SOPs, and your department culture and traditions.

It’s easy to point out what others may be doing wrong, but it takes effort to focus on you and your actions. Use the video footage to help train and benefit you and your department. After all, any one of our departments could be in front of the camera operating for the world to judge. Focus your comments on you and your department, and invest in making them better.

NICK J. SALAMEH is a 36 year veteran of the fire service. He was a Fire/Emergency Medical Services Captain II and previous Training Program Manager for the Arlington County (VA) Fire Department, with which he served 31 years. He is a former Chair of the Northern Virginia Fire Departments Training Committee and was a former volunteer firefighter for the Fairfax County, VA Fire and Rescue Department, Bailey’s Crossroads Fire Station 10. Nick is a contributor to Fire Engineering www.fireengineering.com and Stop Believing Start Knowing (SBSK), https://www.facebook.com/StopBelievingStartKnowing/.