BS EN ISO 13850:2008 Safety of machinery. Emergency stop. Principles for design
BS EN ISO 13850 specifies functional requirements and design principles for the emergency stop function on machinery, independent of the type of energy used to control the function.
It applies to all machinery except for:
BS EN ISO 13850 does not deal with functions such as reversal or limitation of motion, deflection, shielding, braking or disconnecting, which can be part of the emergency stop function.
BSI recommends this version of standard for organisations operating in or with the UK. The ISO edition is available here if required.