The Air Movement and Control Association have revised one of its fan sounds ratings standards.

Standard 301, “Methods for Calculating Fan Sounds Ratings From Laboratory Test Data,” is now known as Standard 301-14 and replaces No. 301-90 and 2006 version, which has been withdrawn.

It sets methods for calculating consistent fan sound ratings from laboratory test data.  It is aimed at fan manufacturers, but others involved in HVAC construction may find it useful to understand how fan sound ratings are created, the AMCA said.