A carbon monoxide (CO) detector signal takes precedence over:

In fire alarm systems, prioritizing signals is crucial for ensuring safety and appropriate response in emergencies. A carbon monoxide (CO) detector signal is considered vital due to the dangerous nature of carbon monoxide exposure, which poses significant health risks even at low concentrations.

When a carbon monoxide detector triggers an alert, it indicates an immediate danger related to CO presence, requiring urgent attention and prompt action. This precedence is based on the fact that CO is a colorless and odorless gas that can lead to unconsciousness or death, making it necessary for such signals to take priority over other types of signals.

Trouble signals indicate issues within the system that may affect its operational integrity, while supervisory signals relate to the monitoring of system conditions to ensure everything is functioning as intended, but neither poses an immediate threat to life. Alarm signals typically indicate a fire situation, but in cases where CO is detected, the health risk associated with CO takes precedence over traditional fire alarm signals.

Therefore, the response of prioritizing a CO detector signal over both trouble and supervisory signals reflects the critical nature of timely intervention regarding carbon monoxide hazards, thus reinforcing the importance of prioritizing life safety above all.