Standards to Bear

A whitepaper by James O’Laughlin, solutions manager, Industrial Safety Systems Division, Sick, Minneapolis, lists standards that are the guidelines behind Sick’s safety strategy.

1. American National Standards Institute (ANSI) consensus standards (e.g., ANSI B11.19: Performance Criteria for Safeguarding Machine Tools)
2. ANSI/RIA R15.06: Industrial Robots and Robot Systems—Safety Requirements
3. European standard EN 954-1: Safety Of Machinery—Safety Related Parts of Control Systems—Part 1: General Principles For Design. The classification levels associated with this standard range from Category B through Category 4, the latter being the most restrictive. EN 954-1 (also known as ISO 13849-1) was superceded by its subsequent version EN ISO 13849-1:2006. This new version of the standard takes both the deterministic measure of safety categories and the probabilistic measures of safety integrity levels and combines these values into performance level classifications. Performance levels (PLs) are based on a number of factors including system structure, reliability, diagnostic coverage, resistance to failure and the process used to determine system function and range from PL ‘a’ to PL ‘e’ with ‘e’ being the most restrictive. Since EN ISO 13849-1:2006 has already been harmonized in Europe, manufacturers of machines destined for Europe generally need to satisfy ISO 13849-1:2006 performance level requirements for machines manufactured in 2010 and later.
4. IEC 61508, the international industrial standard defining safety integrity levels for electrical, electronic and programmable electronic safety components. Before this standard adoption, machine builders and users usually relied on hardwired solutions, like safety relays, to satisfy the requirements of safety-rated control. IEC 61508 provides a framework to ensure that a minimum level of safety is achieved for programmable safety-rated components. Nationally recognized testing laboratories and notified bodies have instituted testing criteria for safety technology developers based on this and other relevant standards.
5. NFPA 79: Electrical Standard for Industrial Machinery
6. EN 62061 – 1: Functional safety of safety-related electrical, electronic and programmable electronic control systems

With requirements of safety components defined, application standards have emerged to incorporate the use of safety-rated programmable components in lieu of hardwired safety control. These application standards include:

1. ANSI / RIA R15.06: Industrial Robots and Robot Systems—Safety Requirements
2. ANSI B11.19: Performance Criteria for Safeguarding Machine Tools
3. EN IEC 60204 – 1: Safety of Machinery – Electrical Equipment of Machines