Managing Alarms.

Jeanine Katzel, Control Engineering

Migration from analog to digital systems has led to abundant, sometimes uncontrolled, alarms. An on-going program to reduce unwanted alarms and monitor, prioritize, and respond appropriately to the rest can keep a plant operating safely and effectively.

Technology is good, so more technology must be better. Right?

Wrong. More is not always better. The advent of the microprocessor and the proliferation of the modern distributed control system (DCS) made it easy to alarm something--everything, in fact--at little or no cost. As a result, many facilities today have an overwhelming number of notifications daily, leading to frustrating, sometimes confusing, and occasionally tragic situations.

"Everyone knows alarm management is important, but somehow it rarely seems to be important enough to justify projects in the plant," observes Todd Stauffer, PCS7 marketing manager, Siemens Energy & Automation. Recent events exposing the consequences of bad alarm management--among them the explosion at the BP refinery in Texas City in March 2005 that killed 15 and injured 170--may be changing that attitude, however. (View a report about the event, attributed in part to alarms that were not fully functional, by visiting the video room on the U.S. Chemical Safety and Hazard Investigation Board Website, www.csb.gov .)

This and other such incidents have prompted personnel at many plants to re-think alarm management programs and look at what has led to the overwhelming number of alarms, learn about and adopt best practices, and promote standards development. The renewed interest has led companies to consider and incorporate benchmarks such as the Engineering Equipment and Materials Users' Association's (EEMUA) Publication 191; "Alarm Systems: A Guide to Design, Management and Procurement," called by many the de facto alarm management standard. Notes Tim Donaldson, director of marketing at Iconics, "Alarm distribution, tag frequency/chattering, cross-correlations, operator response time and operator changes by interval are among reporting metrics that are part of EEMUA and provide valuable information to improve plant operations." In addition, end-users and vendors alike are supporting such standards development as ISA's SP-18.02, Management of Alarm Systems for the …