This International Standard specifies a method for determining the emission sound pressure levels of machinery or equipment, at a work station and at other specified positions nearby, in situ. A work station is occupied by an operator and may be located in open space, in the room where the source under test operates, in a cab fixed to the source under test, or in an enclosure remote from the source under test. One or more specified positions may be located in the vicinity of a work station, or in the vicinity of an attended or unattended machine. Such positions are sometimes referred to as bystander positions. Emission sound pressure levels are determined as A-weighted levels. Additionally, levels in frequency bands and C-weighted peak emission sound pressure levels can be determined in accordance with this International Standard, if required. NOTE 1 The contents of the series ISO 11200[15] to ISO 11205[19] are summarized in ISO 11200[15]. Methods are given for determining a local environmental correction (subject to a specified limiting maximum value) to be applied to the measured sound pressure levels in order to eliminate the influence of reflecting surfaces other than the plane on which the source under test is placed. This correction is based on the equivalent sound absorption area of the test room and on radiation characteristics (source location or directivity at the work station).