| 6.6003.2a
Wiring | Wiring will be installed by a properly licensed contractor, as required by the authority having jurisdiction Wiring will be installed in accordance with original equipment manufacturer specifications, and local and national electrical and mechanical codes | Prevent an electrical hazard |
| 6.6003.2b
Access | Fan and
service switch
Service switch
An electrical switch that controls the complete flow of electricity to a mechanical device
will be accessible for maintenance according to
NFPA
NFPA
National Fire Protection Association, www.nfpa.org
70 National Electric Code or local authority having jurisdiction | Fan and
service switch
Service switch
An electrical switch that controls the complete flow of electricity to a mechanical device
will be accessible for maintenance |
| 6.6003.2c
Fan mounting | Fan outlet will be oriented toward the final termination location Fan will be oriented so the equivalent length of the duct run is as short as possible Fan will be mounted securely in accordance with manufacturer specifications Fan will be isolated from the building framing unless specifically designed to be directly attached Fan will be installed remotely by installing ducting from intake grille | Ensure short duct run to achieve optimum air flow Ensure fan is installed securely Ensure fan housing or building framing does not shake, rattle, or hum when operating Minimize noise |
| 6.6003.2d
Backdraft damper
Backdraft damper
A damper that allows air to flow in only one direction
| A
backdraft damper
Backdraft damper
A damper that allows air to flow in only one direction
will be installed between the outlet side of the fan and the exterior | Prevent reverse air flow when the fan is off |
| 6.6003.2e
Duct connections | Ducts will be connected and sealed to the intake fan and termination fitting as follows: - Round metal-to-metal or metal-to-PVC connections will be fastened with a minimum of three equally spaced screws
- Other metal-to-metal or metal-to-PVC connections will be securely fastened and sealed with welds, gaskets, mastics (adhesives), mastic-plus-embedded-fabric systems or tapes
- Flexible duct-to-metal or flexible duct-to-PVC connections will be fastened with tie bands using a
tie band
Tie band
A strap, often made of nylon, that mechanically squeezes a flexible duct to a fitting. Must have a minimum performance temperature rating of 165° (per UL 181A-type test) and a minimum tensile strength rating of 50 pounds
tensioning tool
- PVC-to-PVC connections will be fastened with approved PVC cement
- Other specialized duct fittings will be fastened in accordance with manufacturer specifications
- In addition to mechanical fasteners, duct connections will be sealed with
UL
UL
Underwriters Laboratories
181B or 181B-M listed material
| Exhaust from desired location to outside Preserve integrity of the duct system and building
envelope
Envelope
The separation between the interior and exterior environments of a building that includes a combination of air and thermal barrier
|
| 6.6003.2f
Boot to interior surface seal | Sealants will be compatible with their intended surfaces Sealants will be continuous and meet fire barrier specifications | Prevent air leakage around intake housing Prevent a fire hazard |
| 6.6003.2g
Air flow | Air flows in
CFM
CFM
Cubic feet per minute
will be measured and adjusted to meet the design requirements | Exhaust sufficient air from desired locations to outside |
| 6.6003.2h
Preventing air leakage caused by exhaust fans | Leakage to the house from other spaces will be prevented (e.g., garages, unconditioned crawl spaces, unconditioned attics) | Ensure occupant health and safety |
| 6.6003.2i
Combustion safety | Pressure effects caused by fans will be assessed and corrected when found outside of combustion safety standards Exhaust fans and other exhausting systems shall be provided with makeup air or other pressure relief | Ensure safe operation of combustion appliances |
