Siam Commercial Bank, Bangkok. Source: Flickr
Eight people have been killed at the head office of one of Thailand’s largest banks when workers accidentally released fire-extinguishing chemicals while upgrading the building’s safety system.
Seven others were injured in the incident on Sunday night in the basement of the Siam Commercial Bank’s main office in Bangkok.
The bank announced that an initial investigation found that “negligence on the part of our contractors hired to improve fire protection in the building” caused the accident.
Contractors working on the fire-extinguishing system in the bank’s basement caused the release of Pyrogen aerosol, the bank said.
“The work may have triggered the Pyrogen aerosol which, once it works, will decrease oxygen, that could cause people’s injuries and death,” a statement from the bank said.
The accident happened late on Sunday in a basement security vault filled with documents.
Pyrogen is a fire retardant intended to starve a fire of oxygen and is designed to be used in places where water would damage documents or equipment.
Pyrogen’s website says the dense aerosol is “most effective in unoccupied areas”, adding that people should avoid exposure to Pyrogen and any “accidental exposure to the aerosol should be limited to five minutes”.
Major-General Porn Sutheerakhun, head of Thailand’s Institute of Forensic Medicine, said initial autopsy results showed the victims suffocated from a lack of oxygen. “There were no wounds found on their bodies. It was like they were sleeping,” he told the media.
Investigators have been searching for clues to how the fire defences was triggered and why victims failed to escape the cloud of chemicals.
“It’s too early to say who is to blame. We need time for experts to investigate the details,” announced acting Bangkok police chief Lieutenant-General Sanit Mahathavorn.
Police Major-General Thawatchai Mekprasertkul said there was no evidence of a fire or explosion that might have triggered the retardant.
Rescuers navigated clouds of chemicals to reach victims. Firefighters, wearing masks and handkerchiefs over their faces, were seen carrying workers on stretchers from the thick, pale smoke.
Bodies were brought out wrapped in white blankets while paramedics tried to resuscitate workers on the pavement.
“SCB would like to express its sympathy to those injured and killed,” the bank said, adding that it was cooperating with the police investigation.
The bank said the building was open for business. The dead included a security guard and seven contractors, it added.
The Erawan medical emergency centre in Bangkok said five people died in the bank and three died later at a hospital.
Seven others suffered suffocation-related injuries, including four who remained in a serious condition, Erawan said.