The American Society of Heating, Refrigerating & Air-Conditioning Engineers Inc., Atlanta, is making available copies of its energy conservation standard in PDF form at The download, which is free until April 2012, is made possible through a funding contract with the U.S. Dept. of Energy. ANSI/ASHRAE/IES Standard 90.1-2007, Energy Standard for Buildings Except Low-Rise Residential Buildings, has become the basis for building codes as well as the standard for building design and construction throughout the U.S. The standard was developed in response to the energy crisis in the 1970s.