Methods of acoustic testing and rating of induction units for sound power emission and terminal attenuation.Cross References:BS 350BS 661BS 848:Part 2BS 1042:Part 1BS 2475BS 3638BS 3763BS 4196BS 4197BS 4954:Part 1PD 5686ISO/R 495ISO/R 1680ISO/R 1996ISO/R 2204