ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2pNS11. Six months of continuous measurement of one-hour average sound levels, one mile sidewise from NAS Miramar, San Diego.

Robert W. Young

1696 Los Altos Rd., San Diego, CA 92109-1321

From 18 July 1994 to 17 December 1994, 1-h average sound level was measured continuously by Computer Engineering Ltd. model 493 integrating sound level meter feeding model 238A secondary processor. The time-mean-square average level printed automatically on the hour, and recorded in an RS232C memory for later analysis, is that during the hour preceeding the hour printed. The site of noise monitoring is the roof 7084 Miramar Road, San Diego, about a mile sidewise north of Runway 6L-24R, NAS Miramar. After adjustments to remove steady ventilating and compressor noise, aircraft noise was tabulated for each day as community noise equivalent level (CNEL), the day-evening-night weighted 24-h average level specified for California airports. The 148-day average CNEL was 69 dB. In one week CNEL varied from 58 dB on Sunday to 75 dB on Tuesday. Such noise variability is being investigated in relation to future movement of Navy aircraft from Miramar to NAS Lemoore, and Marine aircraft from MCAS El Toro to Miramar. Also being here reported for 7084 Miramar Road are the A-weighted sound exposure levels (ASEL) in excess of 100 dB; the greatest thus far is 116 dB.