Intrusive Noise and the Ambient Noise Environment

The extent to which an intruding noise source penetrates the general ambient noise environment in a community, serves as a useful indicator of the likely reaction of the community to that noise source. Available techniques using this approach generally provide a measure of community response based upon the absolute difference in level between the intruding and the ambient noise. Such techniques rarely take account of the percentage time for which the intruding noise is audible within the ambient—a question of importance in determining the possible onset of complaints. The major difficulty in obtaining this information concerns the usual need for sophisticated equipment in establishing the appropriate statistical description of the ambient. This paper looks at a simple method based upon a concept of time and position interchangeability whereby it would appear that the required ambient-noise-level picture may be readily obtained with a sound level meter alone. Tentative guidelines for the interpretation of community response to intrusive noise in terms of the developed statistical picture are put forward.