Larry H. Royster
MAE Dept., NC State Univ., Raleigh, NC 27695-7910
Julia Doswell Royster
Environmental Noise Consultants, Inc., Raleigh, NC 27622-0698
Noise exposure data were collected during 1988--1989 home basketball games at North Carolina State University. Thirteen exposure samples averaging 2 h in duration were collected utilizing Larson--Davis 700 noise dosimeters. Measured noise level results were as follows: average unweighted peak pressure was 133.1 dB, average maximum sound level (L[sub A]) was 115.2 dB, and average L[sub Aeq2 h] was 97.1 dBA. The equivalent 40-h exposure level L[sub Aeq40 h] was 84 dBA. As another example of nonoccupational noise exposure, between 1982 and 1994 seven shopping malls in four different cities were visited to establish the sound level distributions. Over 800 noise level samples were obtained. When the data were restricted to malls with at least 500 000 sq ft, it was determined that measured noise levels L[sub A] could be approximated utilizing the following equations (where N is the number of shoppers within a radius of 7.6 m of the measurement location): L[sub A]=61+10 log(N[sup 0.55]), for N(less than or equal to)10, and L[sub A]=54+10 log(N[sup 1.20]), for N>10.