Throughout history, total solar eclipses have been a significant event. In primitive societies, eclipses were viewed with fear or as important omens. In the US, the upcoming “Great American Solar Eclipse” is creating much excitement. From buying “official” eclipse-viewing glasses, to paying $1500 or more…
The March / April 2020 issue of Intech contains an excellent article by Nick Sands and Donald Dunn, the co-chairs for the ISA-18 committee.
The article reviews some of the most frequently asked questions on alarm management:
Creating an alarm philosophy document is often the entry point into the ISA-18.2/IEC 62682 alarm management lifecycle. Many tasked with developing one are discouraged by its length and the barriers it creates. When it comes to using the philosophy document, a common concern is that if the…
Todd Stauffer, Director of Alarm Management at exida, takes you through a key part of the Alarm Rationalization process called Alarm Objective Analysis (AOA).
You will learn how to determine what alarms you need (and which one’s you don’t), how to eliminate nuisance alarms, and safely reduce the number…
Successful alarm rationalization combines both art and science. From the scientific point of view, rationalization follows a systematic process that applies alarm management principles to determine whether an alarm is justified (needed) and to document its basis (cause, consequence, corrective action, time to respond) and settings (priority, setpoint) in…
From an operations point of view, one of the significant parts of the ISA-18.2 and IEC 62682 alarm management standards is the endorsement of alarm response procedures. An alarm response procedure, otherwise known as “Alarm Help” or “Alarm Response Manual”, is defined as guidance for response to an alarm (e.g., operator…
One of the more important tasks in the alarm management lifecycle is auditing of the alarm system configuration. Auditing preserves your investment in rationalization, checks for changes that bypassed the MOC process, and helps you to maintain the integrity of the alarm system. Oh, and it also required per…
As discussed in What do Nuisance Alarms, the 80-20 Rule, and Mental Models Have in Common?, there are typically a handful of alarm points (10 to 20) that create the majority of notifications (50-80%) to the operator (referencing the 80-20 rule). These nuisance alarms are affectionately called “bad…
As discussed in Part I, bow tie diagrams provide an easy-to-understand visual representation of risk management information (hazards, potential consequences, barriers, degradation factors and controls). In this article we examine the applicability of bow ties to alarm management.
According to the CCPS book “Bow Ties in Risk Management”,…
Study after study finds that something like 80% of industrial incidents (give or take) are caused by Human Error. Incidents involving human error often include a failure of the operator to respond to an alarm, which is often directly or indirectly caused by nuisance alarms. Poor alarm management has…
US Chemical Safety Board cites lack of Alarm Philosophy, Alarm Rationalization, and State-Based Alarming as Contributing Factors to Blowout in Oklahoma
On January 22, 2018, a blowout and rig fire at the Pryor Trust gas well killed five workers, who were inside the…
As the name implies, the purpose of Safe Operating Limits (SOL) is to define the limits beyond which a process will not intentionally be operated and at which troubleshooting ceases, replaced by pre-determined actions to bring the process to a safe state. Pretty important information. I am sure this is…
Situation: There are three operator consoles (positions) in the same control room. There is one general alarm horn that goes off whenever a new alarm comes in from any one of the three consoles. The horn draws the attention of each of the three operators.
Question: How are the…
Contrary to what you might have guessed, the “Defeat of the Situation Awareness Demons” is not a new video game on XBOX or Playstation. It is a set of eight (8) factors which undermine effective Situation Awareness. It can be applied to operators in process plants to characterize human…
Industry Benchmark Survey on Alarms as Safeguards and Independent Protection Layers (IPLs)
exida recently conducted an industry benchmark survey on the practices for the use of alarms as safeguards and IPLs. With over 200 safety practitioners from around the world providing responses, you can use the survey findings to…
Which one of these layers of protection (operator response to alarm, relief valves, dikes, and safety instrumented systems) is not like the other?
Operator response to alarm (Operator Intervention), because of the “Human” factor.
It is very difficult to calculate the probability…
Similar to the thought experiment “If a tree falls in a forest and no one is around to hear it, does it make a sound?”, we ask - If an alarm is generated, and the operator fails to acknowledge it, was it really an alarm? A prevalence of unacknowledged…
The new and updated version of the ISA-18.2 standard (ANSI/ISA-18.2-2016, Management of Alarm Systems for the Process Industries) has now been officially released. This supersedes the original edition (2009). The new version incorporates feedback from 6+ years in the "field" and includes some updates based on the IEC 62682…
The purpose of an alarm is pretty straightforward - to draw the operator’s attention to an abnormal situation that requires action in order to prevent an undesired consequence. Alarms that don’t meet this principle often become nuisance alarms. A nuisance alarm is defined as:
“an alarm that annunciates excessively,…
Understanding operator decision-making is a good first step in improving operator effectiveness. Operator decision-making depends on the person (their level of expertise) and the situation (how familiar). A popular behavioral model from Rasmussen proposes that operator response can be broken into three levels; skill-based behavior, rule-based behavior, and knowledge-based behavior as shown in…