Flashcards in Chapter 6: Duct systems Deck (21)
Return air ducts, outside air ducts, plenums, or concealed spaces may be of combustible construction when _______.
serving a dwelling unit
Joints of duct systems shall be made substantially tight by means of ______.
tape, mastic, or gasketing
The minimum distance from the ground to any metal duct shall not be less than _______ inches.
Insulation applied to the surface of ducts, including duct coverings, linings, tapes, and adhesives, located in a building shall have a flame-spread index not greater than ________.
The smoke-developed rating of insulation applied to surface of ducts, including duct coverings, linings, tapes and adhesives, located in a building shall be of not more than ___________.
Crimo joints for round ducts shall have a contact lap of at least ________ inch(es).
1 1/2 inches
Electrical wiring in plenums shall comply with ________ and the National Electric Code.
The temperature of air conveyed in approved factory-mace air ducts is limited to _________ degrees Farhenheit.
Horizontal 10 inch diameter round duct shall be supported ot intervals of not more than _________ feet.
Vertical ducts with a diameter of 10 inches shall be supported at intervals not more than ________.
12 feet on centers
Air-moving systems supplyig air in excess of 2,000 cfm shall be equiped with ________.
An auto shut off
What information shall be legibly printed on factory-made air ducts and faced insulation?
Thermal resistance (R) value at installed thickness
Automatic shut off is not required___________.
When rooms have direct exit to the building exterior and the travel distance is less than 100 feet
When smoke detectors are required as part of an automatic shutoff system, they shall be installed in the _______.
Main supply air duct served by such equioment
Where gypsum products are exposed in ducts or plenums, the air temperature shall be restricted to a range from ___________ degrees Fahrenheit.
50 to 125 degrees
Exhaust ducts under positive pressure and venting systems shall not extend into or through _________.
Ducts or plenums
Ducts exposed to mechanical damage by vehicles or from other causes shall be ___________.
protected by approved barriers
The minimum dimensions for access openings for fire dampers shall be_____________________.
Adequate to permit inspetion and maintenance of the damper and its oprating parts
The use of rated corridors in fire-resistive construction to convey air yo or from adjoining rooms is _________.
Prohibited by this code
Each access door for a smoke damper or fire damper shall be labeled with letters not less than ________ inch(es) high.