The Air Movement and Control Association International are calling the adoption of its standards by the International Green Construction Code “a significant milestone.”

The new code, which is aimed at commercial buildings, has certified minimum efficiency levels based on the AMCA’s Standard No. 205, “Energy Classification for Fans.” The standard explains how to calculate the “fan efficiency grade” (FEG) based on aerodynamics.

The higher the rating, the higher the potential efficiency, officials said.

“Having FEG levels specified in the first edition of the IGCC is a big win for AMCA and its members,” said Wade Smith, the AMCA’s executive director. “Millions of fans installed in commercial buildings in the U.S. are wasting energy because they were improperly sized or selected, or the owners opted for lesser efficient models due to the lack of an energy-efficiency metric for fans. AMCA developed Standard 205 and FEG as a fan efficiency metric to help designers, contractors, owners, and code officials improve the performance of air systems in commercial buildings, and we look forward to working with them to consider FEG’s when designing for green construction and higher energy efficiency.”

The international green code will also permit the use of air curtains in vestibules above exterior doors, which the association said will keep warm or cool air inside, saving energy.

“Air curtains are an excellent choice for retail and office buildings, where floor space is at a premium,” Smith said. “Not only are air curtains effective, they have a lower first cost than the second set of doors.”

The International Green Construction Code was written by the International Code Council and the American Society of Testing and Materials, and the American Institute of Architects. It is scheduled to be published in March 2012.