This method objectively categorises sources by determination of the prominence of impulsive sound, with the aim of correlating to community response. This method for measuring the prominence of impulsive sounds is intended for sources not identified as gunfire or high-energy impulsive sound. It typically produces adjustments in the range 0,0 dB to 9,0 dB. These adjustments are intended to be used to categorise the sources as either regular impulsive or highly impulsive sound sources and apply the penalty indicated in ISO 1996-1. However, the adjustments may be applied directly, as is done in NT ACOU 112^[2], and BS 4142^[3]. ISO 1996-2 provides additional guidance for performing these measurements.

The method is intended for use on sources with impulsive characteristics that are not already categorised in ISO 1996-1. A non-exhaustive list of examples includes compressed air release, scrap handling, goods delivery, fork lifts with rattling forks, skateboard ramps, industrial shearing, gas discharges, percussive tools in demolition, powered riveting, etc.

The method is not intended for use on sounds from firearms. Although the measurements of prominence may give relevant results, research has shown the response to these sources is influenced by factors outside of the scope of this document. In addition, the method is not intended to use for high-energy impulsive sound sources as specified in ISO 1996-1.

NOTE      This method is not intended for occupational hearing loss, which is outside the scope of this document.

See Annex A for recommended additional research.