A year of background sound measurements in suburbia

Abstract

An internal research project was undertaken to measure the background sound levels at one location with the same equipment for a full year. A suitable location was identified to allow the equipment to stay in the same place and available to refresh data memory cards and battery power. The sound monitoring was done from October 2020 through November of 2021. The site selected was a typical suburban residential property near a secondary road, but far from other influencing sources of sound like highways and industry. The data set is over 9,000 hourly samples of A-weighted sound levels. For each hour the L99, L90, L50, L10, L01 and LEQ were recorded and evaluated for this study. This paper addresses the compilation of the year worth of A-weighted sound levels. The data set also includes one-third octave band sound pressure levels, but those data have not been considered in this evaluation. The noted sound metrics have been evaluated by month, day of the week and hour. The paper also evaluates the selection of the lowest background sound level that is used in many noise ordinances, including the author's home state of Massachusetts.