Alarm Management (or alarm handling) is an issue for any site or process where there is claimed reliance on human response to an alarm in order to control major accident hazards, and for most organizations the problems start with the fundamental question “What is an Alarm?”
The answer to the question at the most basic level is “An alarm requires an operator to undertake an action in response to an abnormal event”. If it doesn’t then it’s NOT an alarm and it’s either an Alert / Prompt or Message
|Operator Must Act||No Action Necessary|
|Situation / Event||Abnormal||ALARM||ALERT|
Having undertaken numerous alarm reviews / rationalisation projects, in C3’s experience in the majority of cases systems are ‘overloaded’ with so called alarms resulting in it being almost impossible for the operators to actually know which ones are important, and so in the main they are ignored.
Indeed it is common for investigations into major incidents to cite the role played in the event of poorly design alarm systems, for example the staff at Milford Haven Refinery were faced with a barrage of alarms for five hours preceding the incident in 1994. The UK Health and Safety Executive clearly state that;
“There should be a clear link from the site alarm philosophy to major accident hazard risk assessments”
It is therefore essential that those involved in the design or management of alarm systems place the appropriate emphasis on the selection, display and response to alarms, and this can only be achieve by actively managing them.
To help guide companies though the process C3’s TUV certified engineers have developed an Alarm ‘Heath Check’ tool, a tool that has been closely aligned to the methodologies set out in both EEMUA 191 and ISA-18.2.
In addition the C3 team are able to help operators with control room design focusing on the ‘Human’ side of alarms as simply having a control system generate and display an alarm correctly is only half the solution.