School officials shall:

(1) Provide mechanical exhaust ventilation that meets or exceeds the requirements in chapter 51-52 WAC at locations intended for equipment or activities that produce air contaminants of public health importance.

(2) Situate fresh air intakes away from building exhaust vents and other sources of air contaminants of public health importance in a manner that meets or exceeds the requirements in chapter 51-52 WAC. Sources of air contaminants include bus and vehicle loading zones, and might include, but are not limited to, parking areas and areas where pesticides or herbicides are commonly applied.

(3) Use materials that will not deteriorate and contribute particulates to the air stream if insulating the interior of air handling ducts. Insulation materials must be designed to accommodate duct cleaning and exposure to air flow without deteriorating. This subsection does not apply if the local permitting jurisdiction received a complete building permit application within three years after the effective date of this section.

(4) Use ducted air returns and not open plenum air returns consisting of the open space above suspended ceilings. This subsection does not apply to:

(a) Alterations to school facilities;

(b) Additions to school facilities that tie into existing ventilation systems that use open plenum air returns; or

(c) Facilities for which the local permitting jurisdiction received a complete building permit application within three years after the effective date of this section.