At 9 AM on a zero degree day with negative wind chill, a fire alarm with sprinkler system activation came in from a warehouse at a business park in Bartlett, Illinois.

The Bartlett Fire Protection District protects the Village of Bartlett and surrounding unincorporated areas, serving the 46,000 residents from 3 stations. The community includes a large, mixed-use industrial business park, single family homes, duplexes, apartment buildings, a downtown of shops, businesses, and restaurants, a ski resort, and several major companies like a pasta manufacturer, restaurant supply company, and cheese merchant.

The Bartlett Fire Protection District responded to the activation alarm within four minutes with their usual complement of one engine, one truck, one ambulance, and one battalion chief, but it soon became clear this would not be a usual fire. Chief William Gabrenya recounts the incident vividly, “When we arrived, the employees who had evacuated said that boxes were on fire inside. Our battalion chief immediately upgraded to a structure fire response and additional resources were dispatched — three engines, three trucks, three ambulances, additional command staff. We put our preplan for that property in motion. The first engine prepared to make entry on side A with the second due engine assigned to support the sprinkler system. The first due engine entered the A side and encountered heavy smoke. They got 600 feet into the building but couldn’t find the seat of the fire. Visibility was low, sprinklers were operating. It quickly became apparent this was going to be a major incident. We upgraded to a Mutual Aid Box Alarm to bring in additional resources.”

Those boxes that the employees had said were on fire were bankers boxes full of paper records. They were densely-packed, stacked floor to ceiling 45 feet high in a 100,000 sq. ft. building. The aisles between the racks were only five feet wide. “It was overwhelming to stand next to those racks,” Gabrenya remembers. “There were 20-25 aisles that stretched as far as the eye could see. And you could hold your arms out and touch the racks on both sides of the aisle while you looked up 45 feet at bankers boxes towering over your head. It was just unbelievably tight.”

The alarm was upgraded several times. More crews arrived and made entry, searching for the seat of the fire. Then, fifteen minutes into the response, there was a major rack collapse.

Crews were thrown to the ground by the force of the collapse. The Deputy Chief near the doorway was blown out of the building. Five of the tilt-up concrete wall sections cracked. The already difficult conditions rapidly deteriorated. “We pulled everyone out,” Gabrenya remembers, “Called emergency traffic. Did our accountability check and thankfully no one was hurt. We immediately slowed things down even though we had all these units coming in — a dozen apparatus, more chiefs, special equipment. We got all the chiefs together and made a plan for how to get back into the building safely. The second engine had tied into the sprinkler system to support it and we continued that through the entire response. We were able to flow water from the sprinklers for an hour and 45 minutes as we used extreme caution and tried to get to the collapse area to figure out what was burning. All the while, boxes are falling, more racks are leaning over and giving way. But we were able to vent out most of the smoke to improve the visibility to be pretty good and then we were able to see the scale of what we were dealing with.”

Half the storage racks in the building had collapsed in the center of the structure, creating a four-story high pile of smoking boxes, paper, and debris. There was no way to get the debris out quickly and easily. The building was built on spec so there were few openings. The department would have had to take out part of an already damaged building to get the necessary machinery in. Neither the building owner nor company leasing the facility had the necessary equipment on site, so it would be eight hours before it arrived. At an hour and 45 minutes into the incident, Chief Gabrenya made the call to shut down the sprinkler system to focus on a handline onto the still-smoldering debris using an unmanned monitor flowing 250 gal/minute onto the area. But after another 20-25 minutes, it became clear that line wasn’t effective, so they turned the sprinklers back on. Fifteen minutes later, the remaining racks collapsed, taking out the roof and, with it, the sprinkler system. The fire response assumed a defensive posture and poured water on the building from the outside, releasing extra crews to return for rehab or to service.

When the sprinkler engineer pulled the system data after the event, it showed that the six sprinklers flowed a combined 1500 gallons/minute for almost two hours. “One of the biggest things we did right was immediately put someone on monitoring the sprinkler system,” Gabrenya said, “Our Fire Bureau was part of the initial response, and the inspector went into the sprinkler room and stayed there the entire time. We got constant feedback on the functioning of the sprinkler system and were able to use that in our decision making.” The monitoring and management of the contributions of the sprinkler system to controlling the event were critically important.

Another important aspect of the response was Bartlett Fire District’s preplanning process incorporating the fire prevention bureau, fire marshal, and three inspectors. Inspectors, managed by the fire prevention bureau, enter all occupancies into incident management and preplanning software, noting hazards, fire flows, sprinkler system details, hazardous materials, and response plans. The preplanning process identified the documents storage facility as a “high importance building,” which triggered a full facility walkthrough and preplan walkthrough by every crew shift annually. The entire department had walked through that warehouse during the preplanning process. “Arriving crews knew the facility was filled with paper,” Gabrenya said, “They knew what the aisles were like and how high the racks were and that it posed significant challenges. We had discussed during our preplanning walkthrough that, given all that paper, we would have to support the sprinkler system if there was a fire because there wouldn’t be enough water otherwise to control a fire in that facility. We didn’t have to evaluate what to do with the sprinkler system or guess upon arrival. We just did it.”

Because of their thorough preplanning, the responding crews knew the occupancy, the system, and the fire response objectives. They had tactics and a preplan in place, including that the first engine would conduct reconnaissance and the second engine would tie into the sprinkler system to support it. “Having things like that decided ahead of time means that everyone knows what to do as first steps upon arrival and that saves valuable time,” Gabrenya said. “Our preplanning software is tied to the dispatch system and available on a laptop in every response vehicle so the officer can click and look at the preplan while en route to the incident location and get those first steps rolling immediately. Preplanning for this property — floor plans, building layout, plan for initial engines — really helped quickly establish command and control and enable accountability.”

When thinking about lessons learned from the fire for future responses, Chief Gabrenya reflects on four things. “First, you wouldn’t think that a location where you poured 1500 gallons of water a minute for two hours could possibly have a sudden acceleration of fire like this one did, but it happened. We now consider preparing for that type of progressive acceleration by setting up equipment in advance to handle that if it occurs. Second, the doors became blocked by the collapse so at a certain point we were no longer able to get crews deep inside. Then we lost the roof and we set up four trucks to deluge from the outside. Next time, I’d set that up earlier in anticipation of the possibility of rapid acceleration and collapse that blocked access. Third, and this is really for industry, we need more research on these types of racking systems and contents in terms of matching fire load to the sprinkler system and accounting for the weight of water in the calculations of the load bearing capacity of these shelving systems. The added water weight due to fire control and suppression probably wasn’t part of the thinking when the warehouse was designed so those racks couldn’t support the added water load. We need to consider that possibility to our preplanning. And finally, preplanning and training is absolutely critical in a fire like this. There was no substitute for our preplanning process and the fact that our crews had been in that facility and had trained on sprinkler system interaction and our preplan for that property. Those were big factors in a safe outcome.”

As part of their preparation, the Bartlett Fire District continually seeks out training in sprinkler systems to continue to sharpen their personnel’s skills. Their training includes the FM Global Fire Service Learning Network’s Fighting Fire in Sprinklered Buildings program. All 55 Bartlett Fire District employees have completed the program. “The FM Global Fire Service Learning Network modules are used to supplement our hands-on practical training,” Gabrenya explains. “The response has been very good, and we have received positive feedback. The Network is a very helpful piece of our overall training program.”

For Gabrenya, the main takeaway when responding to fires like this in commercial and industrial properties is clear. “Every department needs training in response to sprinkler-protected properties,” he asserts. “Every department needs preplanning for sprinkler-protected properties. Get into new buildings to learn about the occupancy and what is being stored. Learn about the fire suppression system and think through how you will work with it during a response. If you are not doing these things, you won’t have any idea what to do if you have an incident there. You’re going to lose valuable time figuring that out. Give yourself the advantage. Get trained in sprinkler systems and do your preplans now.”