What action must occur if a fixed methane detector malfunctions or fails?

• A. Recalibrate the detector immediately
• B. Cause the equipment or part of the equipment the detector is monitoring to shutdown, Give a visible alarm
• C. Notify the supervisor
• D. Replace the detector immediately

Answer: (B)

When a fixed methane detector malfunctions, the immediate priority is to control the potential source of methane and ensure people are alerted. The detector is part of the safety sequence that guards against undetected gas buildup. If it fails, you can’t rely on its readings, so you must shut down the equipment or the part of the equipment that the detector is monitoring to stop possible methane release, and you must trigger a visible alarm to warn personnel of the fault. This combination both removes the risk area from active operation and ensures everyone knows there’s a gas detection fault and can take appropriate action or evacuate if needed.

Other steps like recalibrating, notifying a supervisor, or replacing the detector are important, but they don’t immediately reduce the risk in the moment the detector fails in the same decisive way as isolating the equipment and raising a visible alarm.