“Closing the Holes in the Swiss Cheese Model”
Layers of protection for abnormal event management can be modeled as slices of swiss cheese according to James Reason. An operator’s response to an alarm is one of the first layers of protection to prevent a hazard from escalating to an incident. This presentation discusses a two-part approach to maximizing the operator’s reliability when responding to abnormal situations (“closing the holes in the swiss cheese layer”).
The first part focuses on following the best practices in the alarm management standards ANSI/ISA-18.2-2016 and IEC 62682. Examples include alarm rationalization to ensure all alarms are meaningful and to capture “tribal knowledge”, prioritization to help operators determine which alarms are most critical, alarm classification, monitoring of alarm system performance metrics, and creation of alarm response procedures. The second part addresses the impact of human factors on operator performance; including how nuisance alarms and alarm floods can lead to errant mental models, attention tunneling, misplaced salience and overall loss of situation awareness. We will also discuss how often “operator error” is really the underlying cause of alarm management incidents.
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.