Systems
A proprietary duct system that has its own inherent fire-resistance rating can be used, or a metallic duct, either field fabricated or UL certified factory-built designs. Field fabricated is typically made from 16 gauge carbon steel, all welded, per local codes, which is then externally treated with fireproofing. Factory-built designs are UL tested to the UL 1978 test standard and are made from lighter gauge stainless steel and offered in single wall and multiple double wall insulated designs. Typical materials used for fireproofing field fabricated designs are:
- ceramic fibres
- rockwool
- calcium silicate
- vermiculite boards pressed and bonded with sodium silicate
- intumescents
- endothermic materials, sometimes on their own, sometimes in combination with ceramic fibre
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Famous quotes containing the word systems:
“The skylines lit up at dead of night, the air- conditioning systems cooling empty hotels in the desert and artificial light in the middle of the day all have something both demented and admirable about them. The mindless luxury of a rich civilization, and yet of a civilization perhaps as scared to see the lights go out as was the hunter in his primitive night.”
—Jean Baudrillard (b. 1929)
“I am beginning to suspect all elaborate and special systems of education. They seem to me to be built up on the supposition that every child is a kind of idiot who must be taught to think.”
—Anne Sullivan (1866–1936)
“The geometry of landscape and situation seems to create its own systems of time, the sense of a dynamic element which is cinematising the events of the canvas, translating a posture or ceremony into dynamic terms. The greatest movie of the 20th century is the Mona Lisa, just as the greatest novel is Gray’s Anatomy.”
—J.G. (James Graham)