I was told that the Safety Automation Market (Safety Systems) was not as “dynamic” as the regular Process Automation Market (DCS/BPCS) and that requirements didn’t change as fast or as often.
However, I feel those voices overlook changes to the safety standards. As an example, and as you probably know, there is a new edition (Edition 2) of IEC61508 that takes effect in January 2012 and there is a vote for a new revision to IEC61511 late this year.
January 1, 2012, Happy New Year and someone moved my cheese…
There are new concepts related to criteria to meet a given Safety Integrity Level added to IEC61508 Edition 2 that might affect compliance of installed or legacy systems, in simple terms redundancy is not enough. I’ll briefly touch on Systematic Capabilities and leave other changes to future discussions.
The new edition to the standard requires the product (hardware, software or both) to be assessed for its systematic capabilities.
This means:
1) the system engineering environment needs to provide sufficient mechanism to ensure implementation according to the product’s safety manual or,
2) following guidelines from IEC61508 3.5.9 Note 3, a systematic capability figure (SC 1 to 4) for an element, with respect to the specified element safety function, the systematic safety integrity of SIL (1 to 4) has been met when the element is applied in accordance with the instructions specified in the compliant item safety manual for the element.
3) these requirements will lead modern safety system vendors to introduce hardware and software measurements to guide or enforce implementation in compliance to the product’s safety manual.
So, long story short. Change is good and necessary and if you don’t believe me ask Sniff and Scurry.
How often did you review systematic capabilities of your safety platform back in the late 1990’s? Let us know your challenges and opinions. Things are changing and we’d like to hear from you.