Carbon monoxide safety#
Boiler rooms are required to be well-ventilated. Sometimes community buildings fill the vents to block cold air coming in. This increases the risk of carbon monoxide poisoning. If the boiler room is not well-ventilated, only enter if the heating has been off for a long time. If you hear an alarm, it could be a carbon monoxide sounder; leave the area immediately.
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(c) Santeri Viinamäki, CC BY-SA 4.0, via Wikimedia Commons
Further reading