UNE-EN 61511-1:2017/A1:2017 Functional safety - Safety instrumented systems for the process industry sector - Part 1: Framework, definitions, system, hardware and application programming Requirements
2017UNE-EN 61511-1:2017/A1:2017 Functional safety - Safety instrumented systems for the process industry sector - Part 1: Framework, definitions, system, hardware and application programming Requirements
2017UNE-EN 61511-1:2017 Functional safety - Safety instrumented systems for the process industry sector - Part 1: Framework, definitions, system, hardware and application programming requirements (Endorsed by Asociación Española de Normalización in June of 2017.)
2006UNE-EN 61511-1:2006 Functional safety - Safety instrumented systems for the process industry sector -- Part 1: Framework, definitions, system, hardware and software requirements