A Safety Function is the action of a collection of equipment to implement automatic mitigation of a particular hazard. It is the job of the Safety Instrumented Function (SIF).
Some examples of common Safety Functions:
Most engineers who design and verify safety instrumented functions (SIFs) understand how hard it is to design a manual proof test with high effectiveness (also called high proof test coverage). Those folks who understand that a proof test is not likely to detect all failures never use simplified equations…
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…