In alarm management, what is the purpose of a deadband in controlling alarms?

• A. A deadband is a threshold below which an alarm won't retrigger, reducing nuisance alarms.
• B. A deadband increases alarm frequency.
• C. A deadband calibrates sensors.
• D. A deadband cancels alarms completely.

Answer: (A)

Deadband provides hysteresis around the alarm threshold to prevent alarm chatter from small fluctuations or noise. Once an alarm has fired, minor back-and-forth changes near the setpoint won’t retrigger it immediately because the signal must move beyond the deadband before the alarm can re-arm. This keeps alarms meaningful and reduces nuisance alerts, without calibrating sensors, increasing alarm frequency, or canceling alarms altogether.