What is Safety?
Ans:- The condition of being protected from or unlikely to cause danger, risk, or injury is called as Safety.
There are so many places safety is used e.g. Functional Safety, Process safety etc.
Here, we are taking about Functional Safety.
Functional safety is a term or name is used to describe the safety system that is dependent on the correct functioning of the sensors, logic solver and final elements to achieve the desired risk reduction level. Functional safety is achieved when every SIF is successfully carried out and the process risk is reduced to the desired level and SIF contains SIS.
SIS it is a combination of Sensors(Input), Logic Solver(PLC) and Actuator(Output).
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| Safety Instrumented System |
It is a system which gets inputs from sensors, buttons, transmitter etc. and gives to logic solver means control processor to prevent or mitigate the the output actuator, valves etc.
SIF:- SIF is Safety Instrumented Function. SIF is designed to mitigate hazardous process or event to a tolerate state or risk level.
SIF is not different from SIS. Every SIF has an assigned to SIL levels depending on the amount of risk that need to be reduced from hazardous event.
Basic Layers of Protection
