This International Standard specifies a method for measuring the emission sound pressure levels of machinery and equipment, at a work station and at other specified positions nearby, in any environment which meets certain qualification requirements.Emission sound pressure levels are measured as A-weighted and, if required, C-weighted peak, and in frequency bands.NOTE 1 The contents of this and related International Standards are summarized in table 1 of ISO 11200:1995.A method is given for determining a local environmental correction (the acceptable maximum value of which is specified) to be applied to the measured sound pressure levels to exclude the effects of reflections from reflecting surfaces other than the plane on which the machinery or equipment is placed. This correction is based upon the mean sound pressure level on a measurement surface, the sound pressure level measured at a specified position, and either an environmental indicator or the equivalent absorption area of the test room. The grade of accuracy of the measurements (engineering or survey) depends upon the value of the local environmental correction.A work station is occupied by an operator. It may be located in open space in the room where the source operates, or in a cab fixed to the source, or in an enclosure remote from the source. One or more specified positions may be located in the vicinity of an attended or unattended machine. Such positions are somtimes referred to as bystander positions.