Control Valve Tamper Switches

Q: Please explain why The Joint Commission standard EP 1 identifies control valve signal devices and valve tamper switches as different pieces of equipment? The only difference I can see would be the bolt-on type tamper used to supervise an OS&Y valve as opposed to a butterfly type valve with a built-in tamper switch. Either way, they do the same thing as sprinkler control valves which are supervised by the fire alarm system, but the EP defines them, and the testing requirements for each differently. Why?

A: I’m not sure which EP 1 you are looking at, but EC.02.03.05, EP 1 says: “At least quarterly, the hospital tests supervisory signal devices (except valve tamper switches). The completion date of the tests is documented.” Nowhere does this EP differentiate between add-on after-market tamper switches for OS&Y valves, and those butterfly type valves which have a tamper switch built inside it. As far as the standard is concerned, a tamper switch is a tamper switch. EC.02.03.05, EP 2 does allow tamper switches to be tested every six months.

The EC.02.03.05, EP 1 and EP 2 are based on NFPA 72 which requires supervisory signal devices such as pressure switches and temperatures switches to be tested quarterly, but does allow tamper switches (which are supervisory signal devices) to be tested semi-annually. Why do tamper switches get a break? I don’t know… the NFPA 72 handbook does not say.