This revised 2019 edition of Standard 62.2 adds a compliancepath that gives credit for particle filtration, distinguishing between balancedand unbalanced ventilation system interactions with natural infiltration, requiringcompartmentalization limits for new multifamily dwellings, and allowing forsingle-point envelope leakage test results to be used when calculatinginfiltration credit.Standard 62.2 defines the roles of and minimum requirements formechanical and natural ventilation systems and the building envelope intendedto provide acceptable indoor air quality in low-rise residential buildings. Asin the previous editions of this standard, there are three primary sets ofrequirements and a number of secondary ones. The three primary sets involvewhole-building ventilation, local demand-controlled exhaust, and sourcecontrol. The secondary requirements focus on properties of specific itemsneeded to achieve the main objectives of the standard. Standard 62.2 applies tospaces intended for human occupancy within single-family houses and multifamilystructures, including manufactured and modular houses. This standard does notapply to transient housing such as hotels, motels, nursing homes, dormitories,or jails.The standard considers chemical, physical, and biologicalcontaminants that can affect air quality. It does not address thermal comfortrequirements, specific pollutant concentration levels, or certain potentialpollutant sources such as unvented combustion space heaters and contaminationfrom outdoor sources or from episodic occupant-controlled events such aspainting, smoking, cleaning, or other high-polluting events.