"This standard is limited to gearmotors designed and rated in accordance with Standard AGMA 460.05@ ""Practice for Gearmotors Using Spur@ Helical@ Herringbone and Spiral Bevel Gears@"" or in-line reducers and increasers designed and rated in accordance with Standard AGMA 420.04@ ""Practice for Enclosed Speed Reducers or Increasers Using Spur@ Helical@ Herringbone and Sprial Bevel Gears."" This standard is limited to gears operating at a maximum pitch line velocity of 5000 fpm and a maximum speed of 3600 rpm. This standard includes the instrumentation and procedure necessary for the determination of the gear unit sound level or octave band sound pressure levels. Compliance with this standard does not constitute a warranty of the measured gear unit sound levels under installed field service conditions. This standard covers only those gear units which are lubricated in accordance with manufacturer's recommendations and tested in a system of connected rotating parts free from serious critical speeds@ torsional vibrations and overloads. Purpose There is a need in the gear industry for a sound standard for industrial gear units to improve communication and understanding between the gear unit manufacturer and purchaser. The purpose of this standard is to present the instrumentation and procedure to be used for sound measurements of gearmotors and in-line reducers and increasers as well as to present typical maximum sound levels (A-weighted sound pressure levels). Definitions used in this standard are given in Appendix A."