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QUALIFIED ENGINEERING ASSISTANCE IS AVAILABLE TO COMPOSE SPECIFICATIONS FOR EACH INDIVIDUAL PROJECT.
DUCTWORK
SINGLE WALL (MONOXIVENT 824 LOW SMOKE) AND
PRE-INSULATED DOUBLE WALL (MONOXIVENT 824-API)
Ductwork, including fittings, shall be constructed of filament wound fiberglass reinforced plastic, as manufactured by Monoxivent. The resin shall be Monoxivent 824 Low Smoke.
All surfaces of Duct and fittings, as a finished composite will meet the Flame and Smoke requirements of the Class 1 duct per UL 181 and UMC 10-1. Liners, and or coatings, are not acceptable. Verifications of performance shall be done by an ASTM E-84 testing laboratory recognized by the following building code organizations under the Council of American Building Officials: ICBO; BOCA; SBCCI
Wall thickness shall comply with SMACNA, ASTM D 3982 and NBS PS 1569 fiberglass duct standards. The ductwork will be furnished with the following minimum wall thickness .0125” for ducts up to 20” in diameter, 0.187” for ducts 21” to 36” in diameter, and .025” for ducts 37” to 60” in diameter.
Rectangular ductwork thickness will be determined by substituting the long side for the round diameter.
Underground supply and/or return air plenums shall be made of the same material as the duct.
Monoxivent 824-API pre-insulated double wall duct will have 1” of insulation, with a k factor of 0.14 and R value of .7.
Insulation shall be laminated in place at point of manufacture.
REQUIREMENTS OF A CLASS 1 DUCT PER UL 181 AND UMC 10-1
Flame Spread: less than 25
Smoke Development: less than 50
Fuel Contributed: less than 10
Additionally, the resin shall conform to or be less than the values of the New York State Fire-Gas Toxicity Data.