In an ideal world, every alarm would indicate a malfunction or abnormal condition that required operator action. In the real world, alarms that are irrelevant or annunciate excessively—otherwise known as nuisance alarms— can overload operators with nonessential noise and desensitize them to the importance of alarms (“I can ignore this alarm….”). The presence of nuisance alarms is a common contributor to alarm management incidents.
Alarm shelving provides a way for the operator to manage these nuisance alarms safely and securely. Shelving provides a controlled mechanism for the operator to temporarily remove a nuisance alarm from view until the underlying problem can be addressed. It is such an important tool for alarm handling that it is now required control system functionality per ISA-18.2-2016 and IEC 62682 (Management of Alarm Systems for the Process Industries). As a result, more and more control systems have added this as a standard feature.
Todd Stauffer, PE, is responsible for exida’s alarm management products and services (training, consulting, SILAlarm™ rationalization software). He has been an editor and voting member of the ISA-18.2 standards committee on alarm management since 2005. He was an active participant in the development / publication of the ISA-18.2 standard itself and as an editor / reviewer for ISA’s series of technical reports on alarm management (including ISA-18.2 TR1 “Alarm Philosophy” and TR3 “Basic Alarm Design” for which he served as co-chair). He is currently the co-chair of the joint working group developing ISA-84.91.03 “Functional Safety of Safety Controls, Alarms, and Interlocks for the Process Sector”. Todd is an instructor for ISA’s official training class on alarm management and is exida’s representative on the EEMUA 191 committee.
He has executed numerous alarm philosophy workshops, gap assessments, and alarm management training classes for different control system platforms. Todd developed exida’s alarm philosophy best practices template. He is also the product manager for the SILAlarm rationalization software tool. Todd is an industry thought leader in alarm management. He has published numerous articles and presented many papers at supplier user group and industry conferences. His presentations have garnered three “Best in Conference” nominations and his article “Don’t be Alarmed: Avoid Unplanned downtime from alarm overload“ was selected as Intech magazine’s best article of the year in 2007.