PRODUCT COVERED
Gray Flex System - Flexible Air Ducts - UL 181
The Gray Flex System is also provided under the product name Quality Flex.
PRODUCT DESCRIPTION
The duct consists of a wire helix reinforced film core, wrapped with a fiberglass insulation which, in turn, is covered with a vapor barrier material.
MODELS
Air ducts, Class 1, flexible; sizes 2 through 20 in.
RATINGS
| UL 181 |
Reaction to Fire Classification |
Insulated flexible duct |
Class 1* |
FLAME SPREAD RATINGS
| Test Standard |
Flame Spread |
Smoke Development |
| UL723 |
25 or less |
50 or less |
*Class 1 – Air ducts and air connectors having a flame-spread index of not over 25 without evidence of continued progressive combustion and a smoke-developed index of not over 50.
LIMITATIONS
Maximum Rated Velocity: 5500 FPM
Maximum Rated Positive Pressure: 10 in. W.C.
Maximum Rated Negative Pressure: 1/2 in. W.C.
The following ratings are applicable when the reinforced core construction is used:
Maximum Rated Velocity: 5500 FPM
Maximum Rated Positive Pressure: 15 in. W.C.
Maximum Rated Negative Pressure: 3/4 in. W.C.
Note: A representative sample of the listed devices has been tested, investigated and found to comply with the requirements of the Standard(s) for UL 181, "Standard for Factory Made Air Ducts & Connectors" and are identified with the ETL Listed Mark.
