Before revision: 300px|Carbon monoxide detector connected to an electrical outlet Carbon monoxide alarm A carbon monoxide detector , CO detector, or carbon monoxide (CO ) alarm is a device that detects the presence of carbon monoxide (CO) gas and sounds an alarm in the presence of dangerous levels, to protect against often fatal carbon monoxide poisoning to prevent carbon monoxide poisoning.
After revision: 300px|Carbon monoxide detector connected to an electrical outlet Carbon monoxide alarm A carbon monoxide detector or CO detector is a device that detects the presence of carbon monoxide (CO) gas the to prevent carbon monoxide poisoning.