scope:

Instrumented Protective Systems (IPS) are any instrumented function designed to protect against a hazard with any integrity. IEC 61511-1 places specific requirements on Safety Instrumented Functions (SIFs), which are IPS protecting safety hazards with a required integrity of SIL1 or above.

This guidance should be applied to IPS which are SIFs, but may also be applied to other IPS, including those protecting non-safety hazards or those with below SIL1 integrity.

Purpose

This publication gives good practice in carrying out proof testing of Instrumented Protective Systems (IPS) and writing proof testing procedures, which may assist in fulfilling some of the requirements of Clause 16 of IEC 61511-1. It is intended to both overview the high level requirements on proof testing, including the intent behind the tests, and to give detailed guidance on designing tests for particular instrument types.

Overall requirements for proof testing of IPS and how this is related to the safety lifecycle is established in other documents (e.g. IEC 61511).

This publication is intended for site engineers working with system designers on new IPS, but is also helpful for legacy IPS where documentation of the design is incomplete.