I am often asked whether extending proof test intervals will be a problem.
This is a tricky question. The design and engineering SIL calculations for the Safety Instrumented Functions (SIFs) are taking credit for a specific proof test interval with a defined level of coverage, as defined within the…
In Part 1, we covered the emerging trends in the valve assembly market, how these trends relate to IEC 61511 requirements, and the anatomy of final elements. In Part 2, we discussed the need to show requirements traceability down through the design of the safety instrumented function…
During an IACS cybersecurity risk analysis, each zone of a network is given a target security level. The levels are one to four, with one being the least amount of protection and four giving the most protection. For each zone we ask, “How much cybersecurity protection do we…
Operations and facility managers have a level of responsibility that requires a great deal of judgment, technical understanding, and the ability to make the right call when managing risk.
Safe, secure, and profitable plant operations are the cornerstones of how a plant manager is judged. The plant manager relies…
Last week I attended the ISA Water/Wastewater and Automatic Controls Symposium in Bethesda, Maryland. The conference was attended by equipment manufacturers and municipalities, but system integrators composed the largest group. The technical sessions mainly discussed new opportunities for implementing the industrial internet of things (IoT) and cybersecurity…
In an ideal world, every alarm in a process control system 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 pop up occasionally to quite frequently. They pose a risk to the…
There’s a lot that exida does behind the scenes to advance the industry and benefit you. We try to make sense of data that we collect and put it to good use. One thing we found is that human activities play a role in functional safety, often causing the intended safety performance…
As the incidence of cybersecurity threats in automation systems continue to rise, the automation world continues to grapple with how to address these issues. There are many good practices published in the IEC 62443 series of standards available to end users such as creating demilitarized zones between the business…
Prescriptive BMS standards contain a wealth of knowledge on combustion hazards, unit sequence of operation, and the equipment configuration required for combustion safeguards and combustion control. This experience cannot be overlooked; there is just not a Safety Lifecycle to tie in the Functional Safety Management of the BMS.
That…
By now we’ve all become familiar with safety integrity levels (SIL), as they have become part of our everyday lives. However, with the recent release of several cybersecurity standards in the IEC 62443 series, things are getting more complicated. This series of standards introduces two more levels…
The IEC 62443 series of cybersecurity standards include over ten documents covering various subjects. Buying a full set is a bit expensive, but for me the real cost is the time needed to read and understand them. So I often ask one of the experts at exida…
The idea that diagnostics are useless contradicts everything I’ve ever learned and taught about diagnostics.
Diagnostics help identify problems. Diagnostics can turn a fault that is unrevealed during normal operation into a detected fault, which allows me to take action. That action could be an automatic transition to the…
In Part 1, I covered the emerging trends in the valve assembly market, how these trends relate to IEC 61511 requirements, and the anatomy of final elements.
Now let’s discuss why we need to show requirements traceability down through the design of the safety instrumented function and then…
It always amazes me that when teaching our FSE 100 Functional Safety Engineering course, the number of times I find that end users in the class are not really measuring the performance of their SIS. In most cases, they are doing some measurements, but not thoroughly.
It…
While discussing functional safety certification of an integrated valve assembly with a manufacturer, exida stated that all devices (actuator, pneumatic parts, valve, etc.) must be IEC 61508 certified. The manufacturer said this was no problem, and provided a set of exida and TÜV certificates.
Of…