Machine safety at CNC: emergency stop guards and the rules behind
From AT guidance B.1.3 to the new machinery regulation — and the habits that keep fingers and eyes whole
A CNC machine can move a rotating tool faster and more precisely than any human — and it does not stop because a hand is in the way. Serious accidents in the metal industry typically happen with moving machine parts, rotating workpieces, chips and flung debris. Safety is therefore not a supplement to the trade, but part of the craft itself, and something the apprentice must master from day one in the workshop.
§Shielding keeps you out of the danger zone
The most important protection is physical guarding: gates screens and grilles that prevent access to the hazard zone while the machine runs. On a modern CNC milling or turning machine the gate is often interlocked so the machine cannot start a dangerous movement while it is open. Screens and guards must always be in place and in working condition — it is not permitted to operate a machine with the guard removed or defective. On automated systems light curtains and safety mats are also used to stop the machine if someone approaches.
§The emergency stop: the last resort.
The machine must be equipped with one or more emergency stops that can quickly stop a dangerous movement. The emergency stop is designed so it remains in stop position after activation — it must be actively released and the machine consciously restarted so it does not suddenly start again on its own. The emergency stop is a last resort not the daily stop button: good work consists of avoiding the situation where the emergency stop is the only thing between you and an accident.
§Chips and rotating components
Hot, sharp chips are an underestimated danger. Removal of chips must be done regularly and always with the cover open and all machine operation stopped — never with hands in a running machine and never with fingers, but with a hook or brush. With rotating work, loose-fitting clothes, gloves, long hair and jewellery are life-threatening because they can be caught by the workpiece or spindle. Therefore tight-fitting work clothes are worn, hair is tied up and gloves are not used with rotating machines.
§The rules behind: from directive to regulation
New machines on the European market must be CE-marked and meet the basic safety requirements. So far, the basis has been Machinery Directive 2006/42/EC. It is now replaced by the new Machinery Regulation (EU) 2023/1230, which was adopted in 2023 and comes into full application from 20 January 2027. The regulation updates requirements for, among other things, digitalization and cybersecurity. For you at the machine, it means that the requirements for how machines are designed and documented are tightened – but the basic principle remains the same: dangerous movements must be secured.
- 01Never operate a machine with the guard removed or damaged
- 02Test that the emergency stop works, and know where it is before you start
- 03Remove chips only with machine stopped — use hook not fingers
- 04No gloves loose clothing jewellery or loose hair on rotating machines
- 05New machines must be CE-marked according to current machinery rules
“The machine can always be redone. The finger cannot. Prioritise accordingly.”