Hello there George, It has become common over the past few years that non-residential boilers are wired with EPO (emergency, power off) switches just outside each door to the boiler room. This is similar to having fire alarm pull boxes by the exits. I do not know of any jurisdiction that requires it for a residence. On occassion I've seen the 24 volt circuit for the thermostat being switched, which is a bit sketchy. Normally the 120 volt circuit for the controller is switched. The switches used are of the pushbutton type.
