International Mechanical Code Section 501.3 is hereby amended to read as follows:

501.3 Exhaust discharge. The air removed by every mechanical exhaust system shall be discharged outdoors at a point where it will not cause a public nuisance and not less than the distances specified in Section 501.3.1. The air shall be discharged to a location from which it cannot again be readily drawn in by a ventilating system. Air shall not be exhausted into an attic or crawlspace, or be directed onto walkways.

Exceptions:

1. Whole-house ventilation-type attic fans shall be permitted to discharge into the attic space of dwelling units having private attics.

2. Commercial cooking recirculating systems.

3. Where installed in accordance with the manufacturer’s instructions and where mechanical or natural ventilation is otherwise provided in accordance with Chapter 4, listed and labeled domestic ductless range hoods shall not be required to discharge to the outdoors.

4. In the Downtown, as defined in Bellevue City Code 20.50.016 (Land Use Code), mechanical exhaust system discharge may be directed onto walkways if the discharge is located no less than 16 feet above the walkway per Bellevue City Code 20.25A.130D (Land Use Code) or if a reduced height is approved by the Land Use Director taking into consideration factors such as height above walkway, story height of building, horizontal distance from walkway, filtering of exhaust air, or other elements of the design or the site conditions that affect the exhaust air quality and the walkway environment.