D4500

MOTOR COACH INDUSTRIES Pdf Download PDF Report

Exterior Noise Test

Accelerating from Standstill

Date : 2004-11-11
Personnel : T.S., R.C. and S.C.
Temperature (°F) : 56 Humidity (%) : 45
Wind Speed (mph) : 8 Wind Direction : sw
Barometric Pressure (in.Hg) : 30.1
Verify that microphone height is 4 feet, wind speed is less than 12 mpg and ambient temperature is between 30 F and 90 F: true checked by S.C.
Initial Sound Level Meter Calibration: true checked by S.C.
Exterior Ambient Noise Level dB(A): 44.1

Accelerating from Constant Speed
Curb (Right) Side
Accelerating from Constant Speed
Street (Left) Side
Run # Measured Noise Level dB(A) Run # Measured Noise Level dB(A)
1 78.5 1 75.8
2 77.9 2 76.1
3 78.1 3 76.4
4 76.3 4 75.7
5 76.1 5 78.3
Average of two highest actual noise levels = 78.3 dB(A) Average of two highest actual noise levels = 77.4 dB(A)