Question: In this specific case we have a machine, on which belt drives can cause irreversible injuries. Should the emergency stop still have a dual-channel design, even though the danger points are already protected by means of guards?
Answer: The classification of the emergency stop's PLr must be set out in the risk assessment.
Legislation stipulates that a risk assessment must be produced for each machine.
If the emergency stop's PL (Performance Level) is not specified in a C standard, then it must be defined in the risk assessment.
The recommendation is always to classify the emergency stop based on the greatest hazard arising from the machine.