This publication is now available as an eBook. ASHRAE eBooks are formatted as .epub files. To view this format, you must have a reader program installed that supports .epub. Please verify your device supports this format before purchasing. Reader app and device may affect the display of technical information presented, so ASHRAE recommends using a full-size tablet and/or reader with zoom capabilities. Amazon Kindle readers may not support the .epub format without first converting the file. Questions? Contact bookstore@ashrae.org.ANSI/ASHRAE Standard 62.1-2013 supersedes Standard 62.1-2010. It is ASHRAE's primary standard for indoor air quality for buildings except low-rise residential. The 2013 revision adds a number of changes to remove inconsistencies and improve clarity. Other changes include modifying the Zone Air Distribution Effectiveness for underfloor air distribution systems that meet certain conditions, an increase in the required MERV rating for filters upstream of wetted cooling coils, the addition of a performance path for determining exhaust requirements, the addition of refrigerated warehouses to Table 6-1, and modification of the requirements for water used in humidification systems.