Back on March 17, 2011, two firefighters in Canada were killed in a commercial building when the roof caught on fire and collapsed on top of them. The reported conditions of the fire on arrival were light smoke coming from the roof with no visible flame.

Two of the firefighters went in to see what the issue was on the inside of the store and noticed that there was complete visibility on the interior. There were no smoke conditions inside the building at all, and people were still shopping. The shoppers were removed from the building and within minutes thick, black smoke along with visible flames were exiting the roof area. A short time after, the roof collapsed, fatally trapping the two firefighters.

The occupancy was a “dollar store” type of business where there was a drop ceiling hiding the roof line. It was noted afterwards that roofers had been working on the roof that day using a torch to repair the flat roof and had tried to put a small fire out using snow. What was not known was that the fire had extended into the concealed area above the drop ceiling.

This meant that the two firefighters who went inside the store were working underneath a concealed fire and were not aware of it–nor were they aware of the deteriorating conditions of the roof support system. It was a ticking time bomb waiting to go off.

A good tip to employ is the poking of ceiling tiles periodically to check for fire extension. As crews advance into a structure, they can use their pike pole or roof hook to check for any hidden danger. Along with using a roof hook, a thermal imager (TI) can and should also be used. The TI will assist the interior crews with being able to spot heat sources above their heads, seeing heat convection currents, and locating hidden fire in any type of building.

Even with complete visibility inside a store or structure that has a drop ceiling, this will be a good practice to employ every time to avoid being caught in a ticking time bomb situation.             

Equipment needed: Access to a public store with a drop ceiling, roof hook or pike pole, TI  

Goal: To develop a skill set to check the concealed spaces above drop ceilings in a commercial or mercantile store for hidden fire.    

Mark van der Feyst has been in the fire service since 1999 and is a firefighter with the Fort Gratiot (MI) Fire Department. He is an international instructor teaching in Canada, the United States, and India, and at FDIC. He is also the lead author of Residential Fire Rescue (Fire Engineering Books & Video). He can be contacted at Mark@FireStarTraining.com.