Safety integrity level (SIL) is defined as a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction. In simple terms, SIL is a measurement of performance required for a safety-instrumented function (SIF). Electrical, electronic, or programmable electronic (E/E/PE) safety-related systems are designed to implement the required safety functions and execute the necessary integrity to achieve or maintain a secure state for the equipment under control.
Why SIL is important
The International Electrotechnical Commission's (IEC) standard IEC 61508 defines SIL using requirements grouped into two broad categories: hardware safety integrity and systematic safety integrity. A device or system must meet the requirements for both.
One main principle is to separate random failures from systematic failures. Random failures occur at random times, which result from the possible deterioration of one or more mechanisms in the hardware. Systematic failures are determined by certain causes, which can only be eliminated by modifications in the design of the manufacturing processes, operational procedures, documentation or other relevant factors. The challenge is to utilize a method that can detect the safety integrity of a device or system.
Benefits at a glance with Cert.Pros
Cert.Pros offers services for various safety lifecycle activities including the initial concept, hazard analysis and risk assessment, development of safety requirements, specification; design and implementation, operation and maintenance, modification and final decommissioning and/or disposal.
Our methods contain requirements for preventing failures (by avoiding the introduction of faults) and for controlling failures (ensuring safety even when faults are present). These techniques and measures are necessary to achieve the required safety integrity for our client’s products.