CEN/TC 114/WG 6 - Safe control systems

ISO 13855:2010 establishes the positioning of safeguards with respect to the approach speeds of parts of the human body.
It specifies parameters based on values for approach speeds of parts of the human body and provides a methodology to determine the minimum distances to a hazard zone from the detection zone or from actuating devices of safeguards.
The values for approach speeds (walking speed and upper limb movement) in ISO 13855:2010 are time tested and proven in practical experience. ISO 13855:2010 gives guidance for typical approaches. Other types of approach, for example running, jumping or falling, are not considered in ISO 13855:2010.
Safeguards considered in ISO 13855:2010 include:
- electro-sensitive protective equipment, including light curtains and light grids (AOPDs), and laser scanners (AOPDDRs) and two-dimensional vision systems;
- pressure-sensitive protective equipment, especially pressure-sensitive mats;
- two-hand control devices;
- interlocking guards without guard locking.

ISO - Taking over of an ISO Technical Corrigendum

ISO 13849-1:2006 provides safety requirements and guidance on the principles for the design and integration of safety-related parts of control systems (SRP/CS), including the design of software. For these parts of SRP/CS, it specifies characteristics that include the performance level required for carrying out safety functions. It applies to SRP/CS, regardless of the type of technology and energy used (electrical, hydraulic, pneumatic, mechanical, etc.), for all kinds of machinery. It does not specify the safety functions or performance levels that are to be used in a particular case.
ISO 13849-1:2006 provides specific requirements for SRP/CS using programmable electronic system(s).
It does not give specific requirements for the design of products which are parts of SRP/CS. Nevertheless, the principles given, such as categories or performance levels, can be used.

ISO 13849-2:2003 specifies the procedures and conditions to be followed for the validation by analysis and testing of:
the safety functions provided and
the category achieved
for the safety-related parts of the control system in compliance with EN 954-1 (ISO 13849-1), using the design rationale provided by the designer.
This International Standard does not give complete validation requirements for programmable electronic systems and therefore can require the use of other standards.

This CEN Report provides guidance on the appropriate use and interpretation of EN 954-1:1996. It also gives further information on the following topics: - how the control system contributes to reducing risk in the machine; - what is meant by the safety-related parts of the control system in relation to safety functions; - the proper selection and use of the categories; - the role of annex B of EN 954-1:1996.

This standard provides safety requirements and guidance on the principles for the design of safety-related parts of control systems (SRP/CS). For these parts it specifies characteristics and categories required for carrying out related safety functions. It applies to SRP/CSs, regardless of the type of technology and energy used (e.g. electrical, hydraulic, pneumatic, mechanical) for all kinds of machinery. It does not specify which safety functions and which categories shall be used in a particular case.
In the case of using electronic system(s), this standard is applicable if one or more of the following is satisfied:
1) the required performance level (PLr)is a or b, or
2) the safety function is carried out by hardware where the fault behaviour is clearly determined and assessable, or
3) the contribution of programmable electronic systems within the SRP/CS which carries out the safety function is low (e.g. for monitoring) and the  (PLr)is from a to d, or
4) the safety function is carried out by diverse programmable electronic systems  and the required performance level is from a to d. Depending on the application the diverse programmable electronic system consists of diverse application software and/or diverse operational systems and/or diverse hardware and the required performance level is from a to d, or
5) safety-related parts used (including the software) are designed to the requirements of appropriate standards.
NOTE 1   For the definition of required performance level see 3.24.
NOTE 2   The requirements provided in this standard for programmable electronic systems are compatible with the methodology for the design and development of safety-related electrical, electronic and programmable electronic control systems for machinery given in the horizontal application standard IEC 62061 (under preparation in IEC/TC44/WG7).

This European Standard specifies the procedures and conditions to be followed for the validation by analysis and testing of: - the safety functions provided, and - the category achieved of the safety-related parts of the control system, using the design rationale provided by the designer, and in compliance with EN 954-1.

This European Standard provides safety requirements and guidance on the principles for the design (see [clause] 3.11 of EN 292-1 : 1991) of safety-related parts of control systems.For these it specifies categories and describes the characteristics of their safety  functions. This includes programmable systems for all machinery and for related protective devices. It applies to all safety-related parts of cotrol systems, regardless of the type of energy used, e.g. electrical, hydraulic, pneumatic, mechanical. It does not specify which safety functions and which categories shall be used in a particular case.  It applies to all machinery applications for professional and non-professional use. Also, where appropriate, this standard can be applied to the safety-related parts of control systems used in other technical applications.