Explosion launches 1.5 tonne boiler, killing unsuspecting workers when it lands on office 150 metres away

An explosion launched a van-sized boiler through the roof a St Louis box company and sent it soaring more than 150 metres, before it crashed down onto the office of a laundry business, in a bizarre accident that killed three people and injured four others, authorities said.

One person died in the initial blast about 8 am at the Loy-Lange Box Co and two others were killed when the cast-iron boiler landed on nearby Faultless Healthcare Linen, Fire Chief Dennis Jenkerson said.

The explosion appears to have been an accident, but investigators were trying to pinpoint what caused the boiler — estimated to weigh up to 1.5 tonnes — to explode, Jenkerson said. The blast occurred in a largely industrial area of south St Louis.

Two injured victims were in critical condition, and one was undergoing surgery, Jenkerson said. The injured include a linen company worker who was found pinned beneath the boiler, which Jenkerson said was roughly 1.2 metres in diameter and 3 metres long. The boiler was used to produce steam to power the box company’s equipment.

The boiler was still hot when rescuers arrived, the fire chief said.

Though none of the victims’ names has been released, Faultless Healthcare Linen’s chief operating officer, Mark Spence, told the St Louis Post-Dispatch the three victims there were new hires who were filling out paperwork when the boiler came crashing down on them, killing two and injuring the third.