This standard provides minimum requirements for the HVAC system inspection and maintenance practice in new and existing buildings. Where specifically noted in this standard@ different requirements apply. The provisions of this standard do not apply to a. single-family houses or multifamily structures of three or fewer stories above grade; b. HVAC equipment and portions of building systems that primarily provide for industrial@ manufacturing@ or commercial processes; or c. other building HVAC systems or elements of building HVAC systems that this standard specifically identifies. This standard shall not be used to circumvent any safety@ health@ or environmental requirements. PURPOSE The purpose of this standard is to establish minimum HVAC inspection and maintenance requirements that preserve a system??s ability to achieve acceptable thermal comfort@ energy efficiency@ and indoor air quality in commercial buildings.