Equipment and
appliances on roofs shall be designed or enclosed so as to
withstand climatic conditions in the area in which they are
installed. Where enclosures are provided, each enclosure shall permit easy entry and movement, shall be of reasonable
height, and shall have not less than a 30 inch (762 mm) clearance
between the entire service access panel(s) of the equipment and appliance, and the wall of the enclosure. [NFPA
54:9.4.1.1]
Roofs on which equipment and
appliances are to be installed shall be capable of
supporting the additional load or shall be reinforced to
support the additional load. [NFPA 54:9.4.1.2]
Access locks, screws, and bolts shall
be of corrosion-resistant material. [NFPA 54:9.4.1.3]
Equipment and appliances shall be installed in
accordance with the manufacturer's installation instructions.
[NFPA 54:9.4.2.1]
Equipment and appliances shall be
installed on a well-drained surface of the roof. Not less
than 6 feet (1829 mm) of clearance shall be between a
part of the equipment and appliance and the edge of a
roof or similar hazard, or rigidly fixed rails, guards, parapets,
or other building structures not less than 42 inches
(1067 mm) in height shall be provided on the exposed
side. [NFPA 54:9.4.2.2]
Equipment and appliances
requiring an external source of electrical power for its
operation shall be provided with the following:
- A readily accessible electrical disconnecting means within sight of the equipment and appliance that will completely de-energize the equipment and appliance.
- A 120-VAC grounding-type receptacle outlet on the roof adjacent to the equipment and appliance. The receptacle outlet shall be on the supply side of the disconnect switch. [NFPA 54:9.4.2.3]
Where water stands on the roof at the equipment and appliance, or in the passageways to the equipment and appliance, or where
the roof is of a design having a water seal, an approved
platform, walkway, or both shall be provided above the
waterline. Such platforms or walkways shall be located
adjacent to the equipment and appliance and control panels so that the equipment and appliance is capable of
being safely serviced where water stands on the roof.
[NFPA 54:9.4.2.4]