David Collier, Chairperson of the Machinery Safety Alliance and Business Development Manager at Pilz Automation Technology, has written an article for the Machinery Safety Alliance website, ISO 14119 is on the way, saying that the final draft of ISO 14119 (which will also become EN ISO 14119 and BS EN ISO 14119) is being voted upon. When it is harmonised to the Machinery Directive it will replace the older EN 1088 Safety of machinery. Interlocking devices associated with guards. Principles for design and selection.
+++ STOP PRESS +++ 14 November 2013: ISO 14119 has now been published and David Collier has updated his article, the full text of which is available on MachineBuilding.net: ISO 14119:2013, new standard for guard interlocking. +++
ISO 14119 is intended to provide greater clarity for designers and provide them with the justification required to use newer technologies and the cost of what non-technical people might dismiss as 'expensive duplication'. Compared with EN 1088 there are numerous changes in the forthcoming standard, some of which are listed below.
- Fault masking (unintended resetting) when connecting multiple volt-free contacts in series to a monitoring device
- Defeating of safeguards, and different types of interlocking device
- Guard locking - introduction of bistable solenoid interlocks (power to lock, power to unlock) and electromagnetic locks
- Locking devices performing more than one safety function
- The use of fault exclusions (to achieve PLe requires at least two devices)
- Means of emergency release when persons are trapped behind closed guards
- Testing requirements for guards that are only used infrequently
- Levels of holding force required for typical applications
- Levels of coding required for typical applications
Much more detail about these items is contained in the article ISO 14119 is on the way on the Machinery Safety Alliance website, or register to attend one of the Machinery Safety Seminars organised by the Machinery Safety Alliance. Alternatively, read the updated article on MachineBuilding.net: ISO 14119:2013, new standard for guard interlocking.