Pyrogen system linked to SCB fatalities
THE death of eight people at the Siam Commercial Bank headquarters in Bangkok on Sunday night is suspected to have been caused by a high-tech fire suppression system that became lethal.
The SCB office had suffered a fire previously that destroyed valuable documents.
The system consists of canisters of solid-state pyrogen, which, when activated automatically, releases a gas mainly consisting of carbon dioxide, nitrogen and water vapour to extinguish flames and minimise damage.
But people should not be exposed to the gas for more than five minutes or risk becoming unconscious. Humans can suffer brain damage if deprived of oxygen for more than three minutes and even suffocate to death within 10 to 15 minutes, Ministry of Science and Technology deputy spokesman Worawarong Rakreungdet said.
The commercial fire-extinguishing system was developed based on solid rocket fuel technology, he said. After being activated by an electronic switch or if the canister is exposed to more than 500 degrees Celsius, the gaseous mixture is released to absorb heat and capture hydrogen, oxygen and hydroxide thereby disrupting the oxygenation process and suppressing the fire, he explained.
Pyrogen systems are widely used across Australia, New Zealand, the US, Asia and Africa, Worawarong said. Typically a very small amount of the material is needed to put out a fire, he added.
The system lacks greenhouse gases and is considered environmentally friendly. It is usually used to replace sprinkler systems only in areas where there are not people, such as computer server rooms or document- storage areas, Worawarong said.
