If any detector head senses a gas concentration greater than the set point continuously for how many seconds, the alarm condition is met?

• A. 5 seconds
• B. 10 seconds
• C. 15 seconds
• D. 2 seconds

Answer: (D)

The alarm system uses a rapid time delay to prevent false alarms: the gas concentration must stay above the set point for a short, fixed interval before the alarm activates. In this case, that interval is two seconds. So if any detector head remains above the set point continuously for two seconds, the alarm condition is met. Brief spikes or momentary fluctuations won’t trigger the alarm because they don’t persist long enough. If the level rises above the set point but drops back below within two seconds, no alarm is triggered.