Revised Standard from Last Update.

NATIONAL FOREWORD

This Indian Standard (Part 2) (First Revision) which is identical with IEC 61511-2 : 2016 ‘Functional safety — Safety instrumented systems for the process industry sector — Part 2: Guidelines for the application of IEC 61511-1 : 2016’ issued by the International Electrotechnical Commission (IEC)was adopted by the Bureau of Indian Standards on recommendation of the Industrial Process Measurement and Control Sectional Committee and approval of the Electrotechnical Division Council.

This standard was originally published in 2008 and was identical with IEC 61511-2 : 2003. The first revision of this standard has been undertaken to align it with the latest version of IEC 61511-2 : 2016.

This Indian Standard supersedes the IS/IEC 61511-2 : 2003.

The major changes in this revision are as follows:

a) Guidance examples based on all phases of the safety life cycle provided based on usage experience with IEC61511 1st edition; and

b) Annexes replaced to address transition from software to application programming.

The text of IEC Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain terminologies and conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

b) Comma (,) has been used as a decimal marker, while in Indian Standards, the current practice is to use a point (.) as the decimal marker.