- Pyrogen gas extinguishes fires by removing oxygen needed to feed flames
- Authorities said seven other people were taken to hospitals
According to a statement from Siam Commercial Bank, the contractors died after "a chemical agent used as a fire extinguisher, pyrogen gas, was inadvertently activated and exhausted all the oxygen in the area."
Seven other people were taken to hospitals in the area, the statement said.
Despite initial reports of a fire or explosion at the bank, the company said, firefighters determined there was neither, and the bank opened Monday as usual.
Siam Commercial Bank expressed its "deep regret for those affected, especially those injured and those who lost their lives during this unfortunate incident.
"The bank will provide initial assistance as deemed appropriate. The area is now under investigation by police and concerned authorities," the statement said.
Pyrogen, developed from rocket fuel technology, is a firefighting aerosol that ignites a chemical reaction when fire is detected and immediately removes the oxygen necessary for the fire to burn. It also cools the area, according to pyrogen.com