UL-710:2012 pdf free download – STANDARD FOR SAFETY Exhaust Hoods for Commercial Cooking Equipment.
13 Fire Actuated Damper Assemblies
13.1 Fire actuated exhaust dampers provided as part of an exhaust hood shall comply with all of the following requirements:
a) Fire actuated dampers shall be provided with a heat-responsive device.
b) Fire actuated damper assemblies employing replacement parts, such as fusible links, shall be accessible without the use of special tools.
c) The load on a fusible link used in a fire actuated damper assembly shall be in accordance with the intended use of the fusible link.
d) A manual- or automatic-reset damper operating mechanism shall be capable of closing the fire actuated damper after being subjected to the cycling test specified in Damper Tests, Section 41. A manual-reset damper operating mechanism is one that is required to be manually reset after excessive temperature in the exhaust hood has resulted in the damper closing. All other damper operating mechanisms are to be automatic reset.
e) A fire actuated damper shall remain closed when subjected to the test specified in Damper Tests, Section 41.
f) A spring and a bearing used in the assembly of a fire actuated damper shall be of material having strength and resistance to atmospheric corrosion equivalent to an alloy containing not less than 85 percent copper or Type 302 or 430 stainless steel. In addition a spring shall be of a material having spring properties equivalent to stainless steel conforming to Specification for Chromium-Nickel Stainless and Heat Resisting Steel Spring Wire, ASTM A313.
g) The materials used in tire actuated damper assemblies shall comply with 8.1 and 8.2. The combination of metals used in the assembly of a damper shall not result in galvanic action that impairs the function of any part of the assembly.
Exception: The materials used for the dampers are not required to comply with 8.1 and 8.2 when the damper complies with the Standard for Fire Dampers, UL 555.
13.2 A fire actuated damper shall be installed in the supply air plenum at each point where a supply air duct inlet or a supply air outlet penetrates the continuously welded shell of the assembly. The damper shall be constructed of at least the same gage as the shell. The actuation device shall have a maximum temperature rating of 285°F (141°C). Supply air plenums that discharge air out their face, rather than out the bottom or into the exhaust hood, and which are isolated from the exhaust hood by the continuously welded shell extending to the lower outermost perimeter of the entire hood assembly, do not require a fire actuated damper. See Figure 13.1 for some examples.
13.3 Fire actuated supply air dampers provided as part of an exhaust hood shall comply with the Standard for Fire Dampers, UL 555, in addition to 13.1 (b), (d) and (e).
Exception: Fire actuated supply air dampers that comply with (b) — (g), and are installed in supply air plenums that have been subjected to the fire tests described in Sections 36— 39.