Carbon Monoxide Incident

Fire departments commonly respond on carbon monoxide incidents and they are coded separately in NFIRS.

When carbon monoxide was detected, code the incident as 424 – Carbon Monoxide Incident.

When there was an alarm /detector malfunction, but no carbon monoxide was detected, use
736 – Carbon Monoxide Detector Activation Due To Malfunction.

When there was an alarm activation, no sign of device malfunction, but no carbon monoxide was detected, use
746 – Carbon Monoxide Detector Activation, No CO