I know for safety reason, one machine ,one circuit .I want to know where I can get/find the reg stating you must have only one machine per circuit.

lpdc,

I don't recall a regulation saying that you can only have one machine on a circuit but if you would have two machines on the same cicuit you will most likely pop the circuit breaker especially at the end of the day if you do heat disinfection.

Chuck

Ipdc,
This is a manufacturer recommendation. As Chuck said if you have two or more machines in one circuit and do heat disinfect, you will have problems.