Machine Safety: A new international standard for interlocking devices on guards – ISO 14119: 2013

Have you had unintended consequences of a “temporary defeat” or bypassing guard interlocks? Just-updated ISO 14119 “Safety of machinery – Interlocking devices associated with guards – Principles for design and selection" may help.


Have you experienced any unintended consequences of a “temporary defeat” or bypassing guard interlocks? ISO 14119 “Safety of machinery – Interlocking devices associated with guards – Principles for design and selection" has just been updated and could help mitigate these issues.

A Type B standard, ISO 14119: 2013 updates the previous 1998 edition and harmonizes EN 1088 into one international standard. This update expands original considerations to include additional technologies like RFID and electromagnetic guard locking. It also expands classifications for interlocking devices and provides additional requirements/specifications for installation. Extra care is provided for protection against manipulation of devices and guards in a reasonably foreseeable manner. However, you might find that trapped key systems are not fully addressed in your evaluation and you might find other application standards more helpful like; ISO 13849-1, IEC 62061 or ANSI B11.19.

Generally speaking risk assessments will identify hazards such that when a safety gate is opened, hazardous machine movements must be stopped or reduced to a safe slow speed. The same safety function could also apply to various removable guards, access doors and other points of entry into hazardous situations where interlocking devices are applied. Safety experts are always paying special attention to all precautions, training, signage and engineering methodologies to mitigate hazards to acceptable levels. In my opinion, we should always strive to reduce the possibility to defeat or manipulate all guards maximizing safeguarding levels.

Recently a blog post discouraged the defeating of safety interlocks. At the same time ISO 14119: 2013 for interlocking devices was published and is a positive step in this direction.

Has this presented you with any new perspectives? Do you have some specific topic or interest that we could cover in future blog posts? Add your comments or thoughts to the discussion by submitting your ideas, experiences, and challenges in the comments section below.

Related articles:

Machine Safety: Discourage the defeating of safety interlocks

Machine Guarding & The Hierarchy of Measures for Hazard Mitigation

Machine Safety – serious machine guarding issues!

ASSE - Professional Safety Journal- Near-Miss Reporting, May 2013 

Contact: for “Solutions for Machine Safety”.

No comments
Consulting-Specifying Engineer's Product of the Year (POY) contest is the premier award for new products in the HVAC, fire, electrical, and...
Consulting-Specifying Engineer magazine is dedicated to encouraging and recognizing the most talented young individuals...
The MEP Giants program lists the top mechanical, electrical, plumbing, and fire protection engineering firms in the United States.
Salary survey: How much are you worth?; Dedicated outdoor air systems; Energy models and lighting
Fire, life safety in schools; Fire protection codes; Detection, suppression, and notification; 2015 Commissioning Giants; Emergency and standby power in hospitals
HVAC and building envelope: Efficient, effective systems; Designing fire sprinkler systems; Wireless controls in buildings; 2015 Product of the Year winners
Designing positive-energy buildings; Ensuring power quality; Complying with NFPA 110; Minimizing arc flash hazards
Implementing microgrids: Controlling campus power generation; Understanding cogeneration systems; Evaluating UPS system efficiency; Driving data center PUE, efficiency
Optimizing genset sizing; How the Internet of Things affects the data center; Increasing transformer efficiency; Standby vs. emergency power in mission critical facilities
As brand protection manager for Eaton’s Electrical Sector, Tom Grace oversees counterfeit awareness...
Amara Rozgus is chief editor and content manager of Consulting-Specifier Engineer magazine.
IEEE power industry experts bring their combined experience in the electrical power industry...
Michael Heinsdorf, P.E., LEED AP, CDT is an Engineering Specification Writer at ARCOM MasterSpec.