There is a newer edition of this document available. This Code's purpose is to describe procedures for measuring and reporting airborne sound emissions from mechanical equipment. The outlined measurement procedures can be used to determine compliance with specified acoustical criteria. Measurement procedures in different types of acoustic environments are included. Sound pressure level measurement procedures and sound power level calculation procedures are presented. Generally, sound levels in predetermined frequency bands are used to evaluate mechanical equipment. Operating conditions, environment, and instrument accuracy are described. Instrumentation limitations and environmental conditions pertinent to repeatability and accuracy of test data presented.