§ 4191.16 — Ventilation criteria

4191.16 - Ventilation criteria.

(A) A mechanical ventilation system shall be installed that will provide at least the minimum air circulation and fresh air supply requirements for various uses in occupied rooms without need to open any window, door or other opening to the exterior. (B) Gravity vent openings in the attic shall not exceed code minimum in number and size. The openings shall be fitted with transfer ducts at least three feet in length containing approved internal sound absorbing duct lining. Each duct shall have a lined 90 degree bend in the duct such that there is no direct line of sight from the exterior through the duct into the attic. (C) If a fan is used for forced ventilation, the attic inlet and discharge openings shall be fitted with sheet metal transfer ducts of at least 20 gauge steel, which shall be lined with one inch thick approved duct liner, and shall be at least five feet long with one 90-degree bend, or approved equal. In Subdistrict B or C (noise control areas over 70 Ldn) of the AEO-Airport Environs Overlay District the duct lining shall be at least ten feet long. (D) All vent ducts connecting the interior space to the outdoors, excepting domestic range and dryer exhaust ducts, shall contain at least a ten foot length of approved internal sound absorbing duct lining. Each duct shall be provided with a lined 90 degree bend in the duct such that there is no direct line of sight through the duct. (E) Duct lining shall be a coated glass fiber duct liner at least one inch thick approved and suitable for the intended use. (F) A domestic range shall not utilize a ducted range hood in a residential building. Dryer exhaust ducts connecting the interior space to the outdoors shall contain a baffle plate across the exterior termination which allows proper ventilation. The baffle plate shall be of the same material and thickness as the vent duct material and shall have the same free area as the vent duct. (G) Building heating units with flues or combustion air vents shall be located in a closet or small room closed off from the occupied space by a door or doors to contain noise. (H) Doors between occupied space and mechanical equipment areas shall be solid core wood or 20 gauge steel hollow metal at least one and three-fourths inches thick and shall be fully weather-stripped on all four edges. There shall be no louvers or other opening in any door or wall between occupied space and a mechanical room. All combustion air shall be taken directly from outdoors.

(Ord. 1138-94.)