III. Essential Electrical System
517.25 Scope.
The essential electrical system for these facilities shall comprise a system capable of supplying a limited amount of lighting and power service, which is considered essential for life safety and orderly cessation of procedures during the time normal electrical service is interrupted for any reason. This includes clinics, medical and dental offices, outpatient facilities, nursing homes, limited care facilities, hospitals, and other health care facilities serving patients.
I think the key is orderly cessation of procedures during the time normal electrical service is interrupted for any reason. I think also is key would be the location and design of the unit equipment to the task being performed. I don?t know of a simple answer I feel this issued would be between the electrical engineer and the management of the Health Care facility