Evaluation of aircraft noise measurements

The sound exposure level, SEL, is the measure of noise coming from a single aircraft operation. All SEL measurements, performed in the vicinity of an airport, are aggregated into a few categories of normal distribution. Each SEL category is characterized by the category mean, variance, and the occurrence probability. This study shows how to calculate the overall mean and overall standard deviation of all possible values of SEL from the known occurrence probabilities and the measured category means and variances. The airport noise can be assessed in terms of SEL, but also in terms of the time average sound level, LpAeq,T and the day-evening-night level, Lden. The occurrence probabilities, category means, and variances of SEL are used to estimate the overall mean and overall standard variation of LAeqT and Lden.