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18-28-511.2  Exhaust outlets.
   Outlets for exhaust that exceed 600°F (315°C) shall be designed as a chimney in accordance with Table 18-28-511.2.
   The termination point for exhaust ducts discharging to the atmosphere shall not be less than the following:
      1.   Ducts conveying explosive or flammable vapors, fumes or dusts: 30 feet (9144 mm) from property line; 10 feet (3048 mm) from openings into the building; 6 feet (1829 mm) from exterior walls or roofs; 30 feet (9144 mm) from combustible walls or openings into the building which are in the direction of the exhaust discharge; and 10 feet (3048 mm) above adjoining grade.
      2.   Other product-conveying outlets: 10 feet (3048 mm) from property line; 3 feet (914 mm) from exterior wall or roof; 10 feet (3048 mm) from openings into the building; and 10 feet (3048 mm) above adjoining grade.
      3.   Environmental air duct exhaust: 3 feet (914 mm) from property line; and 3 feet (914 mm) from openings into the building.
Table 18-28-511.2
Construction, Clearance and Termination Requirements for Single-wall Metal Chimneys
 
Chimneys Serving
Minimum Thickness
Termination
Clearance
Wall
Lining
Above Roof Opening (Feet)
Above Any Part of Building Within (Feet)
Combustible Construction (Inches)
Noncombustible Construction
10
25
50
Interior Inst.
Exterior Inst.
Interior Inst.
Exterior Inst.
Low-heat appliances
(1,000°F normal operation)
0.127"
(No. 10 MSG)
None
3
2
18
6
Up to 18" diameter, 2"
Over 18" diameter, 4"
Medium-heat appliances
(2,000°F maximum)
0.127"
(No. 10 MSG)
Up to 18" dia. - 2 1/2"
Over 18" -
4 1/2" on
4 1/2 bed
10
10
36
24
High-heat appliances
(over 2,000°F)
a
0.127"
(No. 10 MSG)
4 1/2" laid on 4 1/2 bed
20
20
See Footnote C
 
For SI: 1 inch = 25.4 inch, 1 foot = 304.8 mm,°C =[(°F)-32]1.8.
a) Lining shall extend from bottom to top of outlet.
b) Lining shall extend from 24 inches below connector to 24 feet above.
c) Clearance shall be as specified by the design engineer and shall have sufficient clearance from buildings and structures to avoid overheating combustible materials (maximum 160°F).