The machine can detect of improper alarms by statistics of the operator's response to alarms.
If the alarm is proper, the operators should most probably respond according to the response procedure defined in HAZOP analysis. Therefore, if according to the statistics, the operator's response is different, this may imply that the alarm is improper.
The system may provide statistics about the operator's response, which may be used to detect and classify improper alarms, based on statistical analysis of the prominent responses, as follows:
| Type of improper alarm | Expected operator's response |
| False alarms | The response associated with corresponding true alarm |
| Irrelevant alarms | Noisy ( no prominent) delayed response |
| Misleading alarms | A response associated with another alarm |
| Distracting alarms | Breaking an unrelated operational procedure |
| Nuisance alarms | Muting the alarm |
| Ignorable alarms | Delay in responding to the alarm |
Updated on 13 Mar 2017.