Assumed 10 Demands Per Year
During a SIF verification calculation review this week, the engineer pulled out a safety certificate with very low failure rates for a solenoid valve. Certificate No. V139 2009 C4-4 [1] states that a solenoid valve has a dangerous failure rate of 4.57…
Cybersecurity continues to be a big problem for the world at large and for control systems specifically. The amount of time and effort that it can take to simply keep all of the security patches up to date on a large control system can be mind boggling. No…
Site Specific vs. Product Specific
During a field failure analysis study, it was discovered that the calculated failure rate of a specific device varied by more than 4X depending on installation site. Particularly, it was one specific site with a high failure rate. While any reliability engineer…
After a false trip incident, I heard a control engineer express his displeasure with the automatic diagnostics in a new safety rated transmitter. The transmitter diagnostics were annunciated by sending the analog current out of range. In this case, the current went to 3.6 milliamps. The problem was that…
I have been doing a number of recent projects introducing the safety lifecycle to companies that are new to the field. As a result I have been playing with various ways to think about the overall safety lifecycle philosophy. As many of the more experienced readers are…
A.K.A You’re About to Severely Under-Design your SIF and Put your People at Risk. Twice this week alone, and much more often than I like to remember, I’ve had safety system designers blindly follow certificates that contain data that simply cannot be true. They get a certificate from…
That is the question.
When your alarm does not meet the definition as defined in the ISA-18.2 standard and/or the criteria established in your alarm philosophy document, it is not an alarm.
By ISA-18.2 definition “an alarm is an audible and /or visible means of…
We’re only human. Most of the time, that is a good thing. But humans seem to accept more risk over time when nothing bad has happened. We lose our vigilance. We take more chances. A close call might only be remembered as an unusually rare anomaly instead of a…
Are alarm classes defined in your alarm philosophy document (APD) as required by the ISA-18.2 standard? The use of classes (classification) is a new alarm management concept for many. If your APD was created before June 2009, chances are alarm classes are not defined.
Alarm…
1. Name your files to make auditing easier; a filename with cryptic job numbers and abbreviations that are used within the company may not be easily understood or cataloged by an auditor
2. Give the auditor the ‘secret decoder ring’ for cryptic company acronyms and abbreviations
3. Have clear…
The old saying goes, “Don’t throw the baby out with the bathwater.” But it looks like a number of people in Australia may be in danger of doing just that with their response to the country’s newly harmonized health and safety laws.
Australia’s new Read More...
How should you react to news of PLC security vulnerabilities?
Project Basecamp was an exercise conducted at the S4 Security Conference that was held last month in Miami, Florida. At the event, six security researchers reported their findings on the…
Many will agree that exida's Safety Equipment Reliability Handbook (SERH) and the Safety Automation Equipment List (SAEL) are very useful tools for choosing products to use in safety instrumented systems. The SAEL shows a product’s IEC 61508 and cyber security…
2011 was a good year in many ways for Functional Safety and Cyber Security. Several instrumentation products achieved IEC 61508 certification. exida Certification alone issued 64 product certifications (http://www.sael-onine.com). With most certification projects, improvements to the design and quality are made. Some manufacturers…
Let me start by wishing everybody a Happy Holidays and Love, Health, Peace, and Safety for 2012. My 5-year old son is very excited about all the holiday decorations. As we celebrate Christmas in my family, we emphasize the birth of baby Jesus as the reason for Christmas, but,…