These cabinets were installed above clothes lockers that were located in a hallway on one of the upper floors in a health care facility. Article 100 defines a “cabinet,” as an enclosure designed either for surface mounting or flush mounting that is provided with a frame, mat or trim in which a swinging door or doors are or can be hung. An enclosure includes the case or housing of apparatus, or the fence or walls surrounding an installation to “prevent personnel from accidentally contacting energized parts, or to protect the equipment from physical damage.”

So, then why isn't this equipment locked? I opened the cabinets while waiting for the elevator. Article 373 covers cabinets. Since there are no “people protection rules” in that location, we have to rely on Article 110. See Section 110-3(a) 8. “Other factors that contribute to the practical safeguarding of persons using or likely to come in contact with the equipment.” See also the definition of “equipment” in Article 100.