Safety-related systems have been used for safety-related functions within the process industry for many years. For process control technology to be used effectively for safety-related functions, it must meet specific minimum requirements and performance levels.
The international standard IEC 61511 covers the application of safety-related systems within the process industry.
It also requires a hazard and risk analysis to be performed in order to work out the specification of the safety-related systems. Other safety systems are only considered in terms of their contribution when examining the performance requirement of the safety-related systems. The safety-related system includes all the components and subsystems required to perform the safety-related function, from the sensor to the actuator.
The "safety lifecycle" and "safety integrity level" (SIL) form the basis for applying this international standard.
The safety-related systems considered in the standard are based on electrical (E) /, electronic (E) / and programmable electronic (PE) technology. If other technologies are used to implement logic control systems, the fundamental principles of this standard should be applied accordingly. This standard also considers the sensors and actuators on safety-related systems, irrespective of the technology with which they are designed.
Within the scope of IEC 61508, the standard IEC 61511 is tailored exactly to the process industry.
