Preview IFA 2015
Almost ten years after it was first published in revised form as EN ISO 13849-1, Safety of machinery - Safety-related parts of control systems - Part 1: General principles for design, the first amendment of this standard is expected to appear by the end of 2015 in a consolidated version.
Since the amendment was intended primarily to improve clarity and ease of application, it contains only a few significant changes.
A number of detail improvements and additions have however been made that are apparent in the standard's practical application.
These include consideration of the probability of occurrence of a hazardous event during determining of the required performance level (PLr), a new simplified method for determining the PL of the output part of the safety-related part of the control system (SRP/CS1) and a proposed method for dealing with the requirements concerning SRESW (safety-related embedded software) when standard components are used.
This paper describes the essential changes. Where the text of the amendment needs interpretation, it provides recommenda-tions.