Report Number: 05-0000166
Report Date: 05/27/2005

Event Description

Early in the morning of October 8, 2003, a box alarm assignment was sent to (a place of worship)at(address). (Dispatch center)received a cell phone call reporting a fire outside the building. When(XXFD)arrived, they discovered a working fire in the church. The fire went to a third alarm assignment. Approximately 45 minutes after the initial call to (dispatch center)the building sustained a structural collapse involving the engineered roof trusses. The firefighters on the scene escaped serious injuries or death only by a combination of luck, divine intervention, and good common sense tactical and strategic decisions by the entire group of officers on the scene. This is a follow-up report to Captain (name deleted)'s initial after action report. The theme of this communication is to bring a level of further awareness to the (fire department)'s personnel of the dangers of truss construction and their behavior under the insult of fire. This report contains information gained from interviews with the officers and some of the firefighters on the scene that morning. The Building (An XXFD chief)researched the building history of the church and could not locate either the original approved plans or identify the building’s architect. The building was built about ten years ago (1993)when the (deleted community name) was developed. The congregation’s original church sat on property that is now developed as part of (deleted community name). The current church building has a main sanctuary and a fellowship hall with attached classrooms. The main sanctuary was separated from the fellowship hall by a brick firewall. The fellowship hall had a kitchen and a large room that served as their fellowship area. This area is directly under the collapsed roof trusses. A very large, dimension lumber dormer fell almost intact in that area. It brought a large section of roof with it and crushed tables and chairs in the fellowship hall to the floor. Anyone that would have been under the dormer would almost certainly been seriously injured or killed by the weight of the dormer and roof sections. The fellowship hall’s roof system had a span of 40 feet. This roof span was made using 2X4 gusset plated scissor trusses on 24-inch centers. There were 20 of these trusses. The design of the trusses created a three to four foot void space at the top of the truss. This void space ran the length of fellowship hall roof, which was 40 feet. This design would play a part in the companies' failure to quickly control the fire. The dimension lumber dormer was stick built with 2 X 6 inch jacks with a 20-foot long 2 X 10 ridge board. It was at least 20’ in front with a depth of 20’ to the fellowship hall roof. The front part of the ridge board was supported vertically by the front bearing wall. The rear of the ridge appeared to be supported only by the plywood on the roof and the spacing of two of the scissor trusses. The roof was covered with asphalt shingles. The fellowship hall had small-pitched roofs over each of the meeting room areas. The Fire The fire began on the outside of the building in a main primary electrical entrance box attached to the building. The (deleted local government name)building standards electrical inspector determined the cause of the electrical box fire to be related to the connection bindings between the (deleted power company name) side of the primary electrical wires and the church’s main electrical wires. The electrical inspector stated to Fire Investigation that this problem has been observed before. Apparently if the connections are not made properly the connection can short out causing fire. The fire apparently burned for some time before a passerby detected it. It entered the building on the D side and burned into the attic of the classrooms and void space in the roof of the fellowship hall. Captain (name deleted)said when Engine (XX, first arriving) arrived there was heavy smoke around the D side of the building. He focused his initial efforts on command activities while his two firefighters extended a line into the building. The reports from his firefighters were that the fire was in the electrical panel only. They called for a CO2 extinguisher to fight the electrical fire. Apparently all on scene at that time underestimated the extent of the fire. It had already entered the large void area in the fellowship hall roof system’s trusses. There was a delay in getting water on the fire because of the decision to fight the fire with an extinguisher before putting water on the burning structural members. Engine (XX, second arriving) had gone to the wrong location and had a delayed response. The only companies Captain (name deleted)had on scene during the initial attack were his crew, Ladder (XX) and Engine (XX, second due). Engine (XX, second due)was assigned a water supply and then a primary search. Ladder (XX)'s crew, under the command of Captain (name deleted), began roof vent operations shortly after their arrival. Captain (name deleted) stated that she observed the roof to be very soft as they arrived at the end of the aerial ladder. She directed her crew to vent the roof from the safety of the ladder. They vented the roof very early in the incident. When the vent operation was completed, a large volume of fire emitted from the vent hole. Captain (name deleted)arrived as Acting Battalion (XX) at 0415. After a short transfer conversation, he assumed command. He pulled a second alarm at 0420. For the next 12 minutes the firefighting efforts were concentrated on finding access to the fire above their heads. The fire continued to free burn in the roof void space. There were three 1-¾" handlines in service in the fellowship hall. All the crews on scene apparently were not aware of the existence of the large void area in the roof truss. The scissor trusses created a vaulted ceiling in the main fellowship hall. Interviews with the firefighters that were inside revealed that there was little smoke and heat at the floor level. They were also unaware of the serious fire conditions at the roof level. Captain (name deleted)did observe those conditions from the outside. As the firefighters' air supplies on their initial SCBA tanks ran out, they began to exit the building. By 0434 extra companies had arrived on the second alarm and began to replace the first alarm assignment. Captain (name deleted)stated that as this was occurring, he heard and saw a large part of the fellowship hall ceiling collapse. At that time he ordered everyone out of the structure. He initially ordered the companies out of the building with his radio. Captain (name deleted) remarked that the evacuation was not going as fast as he thought it should so he then ordered (dispatch center)to sound the evacuation tone. Captain (name deleted)and Chief (name deleted) were standing near the A side entrance making sure everyone had made it out when the whole roof collapsed. Both of them stated the down draft of air created by the collapse knocked a helmet off a firefighter standing directly behind them. The stick-framed dormer collapsed almost intact and brought the rest of the roof with it. Both of those officers told me that if anyone had been under the collapse area their chances of survival would have been slim.

Lesson Learned

• Lightweight truss construction will collapse with little or no warning in a fire. The roof system in the fellowship hall collapsed after firefighters had been on scene for about 45 minutes. The only warning sign the IC had to the collapse was the collapse of the ceiling. Had he not ordered everyone out, it would have been very possible one or more crews would have been in the collapse area. • Beware of all large span roof systems. The span of the fellowship hall roof was 40 feet. Most recent residential and small commercial construction utilizes lightweight trusses of either wood or metal to span those distances. From an engineering standpoint these assemblies are very sturdy. However, when insulted by fire, all bets are off. Free burning fires in large span roof systems should necessitate an immediate evacuation of the area under the span. If firefighting efforts have not controlled the fire after ventilation or access to the ceiling areas, there is a high probability that the fire is in a void space that contains web members of a truss. Loss of the web members and gusset plates cannot be seen, but it can be predicted if the IC takes a pessimistic view of the incident. • Firefighter teams have to act as “special forces units” when their officers have command responsibilities. Company members, at times, must be able to act and make decisions without direct supervision of their officers. When a company officer has command responsibilities, their company members must be able to make tactical decisions about hose placement, evaluate fire conditions, call for help, and communicate information to the command officer. Each firefighter has to have the ability to operate on their own within their team to assist the initial IC in making the right calls in the first few minutes of the incident. • Initial IC’s must assign officers to the interior of a structure as soon as possible. When the first due officer has command responsibilities in the first minutes after arrival they must depend on their crews to operate without direct supervision. Therefore it is critical that once other officers arrive on scene they should be assigned to interior tasks supporting the command officer’s crew. This places an officer with the initial company’s crew ensuring officer level accountability for the tasks. • Life safety is the first priority at emergency incidents. Initial action plans must be developed around the first priority of life safety. This includes firefighters' life safety. Conducting a primary search is critical to any interior fire incident. Ensuring the life safety of firefighting forces is equally critical. Command officers must make initial assignments that take into account the life safety hazards to civilian as well as firefighters. Sometimes the hazards to the firefighters are not so obvious or taken for granted. In truss construction, there are plenty of hidden killers waiting to be unleashed. Complacency on the part of the command officer about truss construction may be fatal. Orders to incoming companies should take into account the size-up for the incident. If the command officer expects a serious civilian life hazard then more emphasis should be placed on an aggressive primary search. On the other hand, if the command officer suspects serious life hazards for the attacking firefighters, emphasis should be placed on tasks that support a safe working environment for firefighters. Firefighters can still do primary searches while putting out fire and pulling ceilings looking for hidden fires. Conclusion The officers and firefighters on the scene that morning probably did not realize they faced a dangerous situation with the roof truss system. There were no outward clues that the large dormer that collapsed was stick framed from solid dimension lumber. The only clue Captain (name deleted)had to the impending collapse was the failure of the ceiling in the fellowship hall. Had he not ordered everyone out, we may have faced a terrible tragedy. The initial interior fire attack was conducted by two firefighters while their officer remained outside in the command mode. The next officer was assigned to conduct a primary search. The initial attack crews underestimated the volume of fire already above their heads in the truss space. They thought the fire was electrically related and requested a CO2 extinguisher to fight the fire. This caused a delay in the time it took to get water of the fire. From all accounts heard about the incident, the fire was stopped before it reached the main sanctuary and there were no firefighter injuries. This is a very positive outcome. After seeing the aftermath of the dormer collapse, the outcome could have been much worse.

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