I hope that everyone doesn’t mind me using this column to highlight some issues with my day job! The fact that I’ve missed the copy date (sorry Phil) and I’ve been neck deep in Ducks (See my last column on Community for details of The Widnes Duck Hunt my community event raising money for Community Defibrillators).
Today I’d like to talk emergency stops. The standard harmonised to the EU Machinery Directive and the designated standard to the Supply of Machinery Regulations in the UK is ISO 13850.
The standard was updated in 2015, yes 11 years ago and actually it is going through its review cycle currently. Why do I tell you this?
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I still see emergency stop buttons on-sale and being installed which comply with the 2006 version of the standard. How do we know?
- White arrows on the red actuator
- Wording on the yellow background disc
Why does it matter you ask?
Well, these changes came about through the international use of the standard. That not only has visual changes but other technical changes.
It was reported that the arrows were causing confusion on the use of the button (twist to use rather than push to use). The writing was delaying use while people worked out what it was!
So, what should they look like?
- Red Actuator
- Yellow Background
- Easily used with palm of the hand
- Key release is discouraged (although allowable).
What else do we need to consider?
The e-stops now need to be a minimum of Performance Level c (ISO 13849) or Safety Integrity Level (SIL) 1 (IEC 62061). Basically, safety components that are hard wired or through a safety PLC.
Must stop all machinery in the line of sight from the e-stop button.
The user must decide whether the machine must stop immediately (Category 0 stop) or can run down with time (Category 1). Then make sure that this is achieved which might include extra measures such as brakes or mechanical pins!
I highlight all of these issues as in 2026 I’m still seeing these issues when completing machinery safety audits / assessments on NEW projects across multiple sites and industries! They are supplementary systems to the other machinery protection systems BUT they are the very last line in defence to stop people being seriously harmed.
In the UK the review of Emergency Stop Controls is covered in law by the Provision and Use of Work Equipment Regulations (PUWER) 1998 Regulation 16! So not only a standard for guidance but included in law to be complied with.
The AI generated image was deliberately asked to show the issues that shouldn’t be present before anyone comments!
Now to all of the vendors that have equipment at trade shows you have been warned of my game – spot the illegal e-stops! I look forward to highlighting your issues!
