ST. STEPHEN, New Brunswick – An explosion in the wood-chip processing building at the Flakeboard Co. Ltd. mill Tuesday forced several firefighters to jump from the roof into the foam they had been using to suppress the fire.

Some of the firefighters were from Calais, and for a few tense minutes it was not known if any had been hurt.

Calais and St. Stephen have a mutual aid agreement, and the two departments regularly assist each other in battling large structure fires.

Around 3 p.m. scanners began to crackle as firefighters from St. Stephen and Calais were called to the mill on Church Street.

When firefighters arrived, flames were pouring from two metal cyclones shaped like conical cylinders located atop the shaker building. Wood chips are processed inside the building before being sent to a large drying drum. The Canadian company manufactures pressed board for the building industry.

“There are a couple of great big shakers [inside the metal building],” Calais Fire Chief Danny Carlow explained. “They are just part of the process of moving the chips and refining them.”

Soon after firefighters arrived it appeared the fire was under control, but suddenly there was a huge explosion and flames shot through the roof. The concussion blew out two side walls, and fire came from the bottoms of two of the cyclones.

“The crew that was on the roof managed to dive into the foam and they weren’t hurt,” Carlow said.

Sirens could be heard coming from several directions as ambulances from St. Stephen and Downeast EMS in Calais rushed to the scene. At one point three ambulances from St. Stephen and one from Calais were in the wood yard.

“That’s why we called for the ambulances, because it took a while to account for everybody,” Carlow said.

The chief said the two side walls were designed to blow out to relieve pressure inside the building. “They did what they were designed to do,” he said.

Firefighters began a second major assault on the flames by pouring water and foam on the fire from a safer distance.

Although there had been a report of minor injuries among mill workers, Carlow said he did not believe any of them required medical attention.

A Calais hook and ladder truck pulled up next to the shaker building and the ladder stretched high above the mill. Calais firefighters climbed to the top of the ladder and shot water inside one of the cyclones. “We needed a large volume of water to go down through those cones [cyclones] to get at the seat of the fire,” Carlow said.

In a moment of comic relief, one firefighter walked up to the news director of WQDY FM and asked him to inform area residents on the radio that the Tuesday night fireman’s bingo at the Masonic Hall in St. Stephen had been canceled.

An acrid chemical smell that burned the throat and mouth hung in the air, and for a time smoke also billowed from a nearby culvert.

An hour after the fire started there was a call for more portable radios as well as foam. And an order went out to open the doors on the filter house and the cyclones. “We poured water into the top of the filter houses and opened doors, and they are soaked completely,” a firefighter said over the scanner.

This was not the first large fire at the mill. In July 1976, thousands of tons of wood flakes piled as high as an eight-story building burned for several hours. Firefighters from both sides of the border battled the fire for hours. A vintage World War II plane from Fredericton, New Brunswick, and a helicopter from the former Georgia-Pacific Mill in Baileyville aided them.

St. Stephen fire officials remained on the scene Tuesday night and were unavailable for comment. “The whole process once it gets going, all works off pumps and vacuum and it just draws it in through the mill so you have to go find it [the fire], find out the furthest point that it went, and start your way back,” Carlow said as he explained the delay in putting out the fire.

For more than 40 years, the Flakeboard Co. Ltd. has provided engineered wood panel products to the North American market.