Introduction in safety rules EN954–1, EN13849 and EN62061

The introduction of the new safety rules, that are replacing the well known EN954-1, that, after the last decision in December 2009 is going to be retired in December 2011, creates some concern in the developers of automation systems for industrial plants, especially in metal industries, due to the nature of the heavy manufacturing process that require a careful evaluation of the safety approaches. Some of the concerns derive from the fact that instead of one there was the introduction of two different rules, the ISO EN 13849 and IEC EN 62061. Moreover, the two rules are not so easy to read and apply because they introduce some statistical parameters that are not usual for system designers. The aim of this paper is to introduce these rules.