well it looks like UMC is based on NFPA
7.8.2 Rooftop Terminations.
7.8.2.1 Rooftop terminations shall be arranged with or provided with the following:
(1)
A minimum of 3 m (10 ft) of horizontal clearance from the outlet to adjacent buildings, property lines, and air intakes
(2)
A minimum of 1.5 m (5 ft) of horizontal clearance from the outlet (fan housing) to any combustible structure
(3)
A vertical separation of 0.92 m (3 ft) below any exhaust outlets for air intakes within 3 m (10 ft) of the exhaust outlet
(4)
The ability to drain grease out of any traps or low points formed in the fan or duct near the termination of the system into a collection container that is noncombustible, closed, rainproof, and structurally sound for the service to which it is applied and that will not sustain combustion
(5)
A grease collection device that is applied to exhaust systems that does not inhibit the performance of any fan
(6)
Listed grease collection systems that meet the requirements of 7.8.2.1(4) and 7.8.2.1(5)
(7)
A listed grease duct complying with Section 4.4 or ductwork complying with Section 4.5
(8)
A hinged upblast fan supplied with flexible weatherproof electrical cable and service hold-open retainer to permit inspection and cleaning that is listed for commercial cooking equipment with the following conditions:
(a)
Where the fan attaches to the ductwork, the ductwork shall be a minimum of 0.46 m (18 in.) away from any roof surface, as shown in Figure 7.8.2.1.
(b)
The fan shall discharge a minimum of 1.02 m (40 in.) away from any roof surface, as shown in Figure 7.8.2.1.
(9)
Other approved fan, provided it meets both of the following:
(a)
The fan meets the requirements of 7.8.2.1(3) and 8.1.3.
(b)
Its discharge or its extended duct discharge meets the requirements of 7.8.2.1(2). (See 8.1.3.)