The door opens, temperature increases, an alarm goes off, the alarm is suppressed. During an all-hands meeting with a full crowd in the break room, the temperature increases, an alarm goes off; the alarm is suppressed.
An operator, Michelle, turns to a fellow operator and says, “Why does that alarm alert every time the room isn’t 68 degrees?”
The other operator responds, “Well, when we set up the system ten years ago, we forgot to give the temperature a range. Never went back in to fix it.”
Nuisance alarms are a pain to respond to continually. But how to make it better?
Often, the answer lies in a combination of a better administration, tuning, and delivery of alarms. Taking the time to identify and change the nuisance alarms will help your facility to have a proactive alarm management system.
The Nuisance Alarm: A House of Cards
Let’s consider some ways that we’ve seen operators handle nuisance alarms:
“This alarm always comes in, and it’s nothing--just ignore it.”
“We know that device has communications issues that cause that alarm--just ignore it.”
“I’m pretty sure Bob’s troubleshooting that right now, and it’s setting off alarms--just ignore it.”
“Every time we get this alarm for X, it really means Y, so ignore X and go look for Y.”
Ignorance is bliss--until it’s not.
The human learned rules applied to nuisance alarms are a sensitive house of cards. While many facilities have these human-created filters when dealing with nuisance alarms, they don’t need to exist. Additionally, each operator has their own internal handling filters, without any documentation or unified rationalization. This can set facilities up for negative consequences when either a serious event occurs or when a new operator joins the team.
Proper Commissioning and Updates
The best way to avoid any of these unfortunate situations is to conduct thorough commissioning of the alarming system AND any alarms introduced after the initial commissioning. If the mission is critical and/or small enough, it may make sense to conduct a point-to-point test of every alarm. However, not every organization has the resources or time available to complete such an extensive process.
In these cases, several alternative methods can be explored. One approach involves introducing a “commissioning mode” for alarms, which redirects the alerts to recipients responsible for evaluating the new alarms’ behavior. After some predetermined soak period, the alarm can be released into production, assuming any issues found by the evaluation team are resolved.
Of course, a commissioning process wouldn’t necessarily prevent the issue of alarms when someone is working on equipment. Luckily, we can expand on the commissioning mode concept with a “maintenance mode.” Like the commissioning mode, maintenance mode alerts are sent to a different distribution list. Since this distribution list will likely include recipients from the production distribution lists, we further qualify the alert with a clear indicator that this is an alert for an asset in need of maintenance.
Finally, we can extend our solution to address alarms that are triggered by communications issues. We can add logic that looks for intermittent, stale, or insufficient data, which indicates the device is not communicating correctly with the platform. The alert is routed to the associated severity group used for communications alarms.
Out-of-Box Nuisance
Another typical nuisance example is a so-called “alarm” that indicates that an asset is performing an expected, regular operation. Many devices and system vendors will err on the side of caution by providing more out-of-the-box alerts than are necessary or lumping status indicators in with real alarms. Unfortunately, this is especially true for devices typically deployed at scale, which means your nuisance alarms will likely show up at a similar scale.
For example, an air handler’s fan switches on, which is most likely NOT an alarm. Instead, it is an indicator that the asset performed an expected operation. First, this alarm should be removed from any alarm severity groups that will generate alerts. Depending on the specific severity group strategy, this type of alarm could be relegated to an information-only severity group, ideally the lowest severity group. Moreover, this type of information should be available as a real-time data stream that can be analyzed in the various aspects (reports, graphics, etc.) of the data infrastructure.
Find the Alarm Relief
Stop the nuisance, and regain control of your alarm system. At Casne, we can help you fix the nuisance alarms and bring your facility peace of mind when it comes to your entire alarm system, including the development of alarm philosophy and rationalization.
Casne Engineering provides all the necessary solutions for your operational technology needs. We bring over 40 years of success in professional engineering and technology integration services for major utilities, process industries, and critical facilities. Our team of capable engineers and technologists develops and supports engineered solutions using the best of breed products and technologies. Contact us here to discuss your operational technology needs.
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