scope:

This part of ISO 13849 provides safety requirements and guidanceon the principles for the design and integration of safety-relatedparts of control systems (SRP/CS), including the design ofsoftware. For these parts of SRP/CS, it specifies characteristicsthat include the performance level required for carrying out safetyfunctions. It applies to SRP/CS for high demand and continuousmode, regardless of the type of technology and energy used(electrical, hydraulic, pneumatic, mechanical, etc.), for all kindsof machinery. It does not specify the safety functions orperformance levels that are to be used in a particular case. Thispart of ISO 13849 provides specific requirements for SRP/CS usingprogrammable electronic system(s). It does not give specificrequirements for the design of products which are parts of SRP/CS.Nevertheless, the principles given, such as categories orperformance levels, can be used.