SAE J1096-2000 pdf download Measurement of Exterior Sound Levels for Heavy Trucks Under Stationary Conditions
1. Scope—This SAE Recommended Practice establishes the test procedure, environment, and instrumentation for determining the maximum exterior sound level of highway motor trucks and truck tractors over 4540 kg gross vehicle weight rating (GVWR) with governed engines under stationary vehicle conditions. The basic procedure involves a full throttle engine acceleration and a closed throttle deceleration with the engine inertia as the load.
2. References
2.1 Applicable Publications—The following publications form a part of the specification to the extent specified herein. Unless otherwise indicated, the latest revision of SAE publications shall apply.
2.1 .1 SAE P UBLICATION —Available from SAE, 400 Commonwealth Drive, Warrendale, PA 1 5096-0001 .
SAE J1 84—Qualifying a Sound Data Acquisition System
2.1 .2 ANSI P UBLICATIONS —Available from ANSI, 1 1 West 42nd Street, New York, NY 1 0036-8002.
ANSI S1 .4-1 983 and S1 .4A-1 985—Specification for Sound Level Meters
ANSI S1 .40-1 984—Specification for Acoustical Calibrators
2.1 .3 ISO P UBLICATION —Available from ANSI, 1 1 West 42nd Street, New York, NY 1 0036-8002.
ISO 51 30-1 982—Acoustics—Measurements of noise emitted by stationary road vehicles—Survey method
2.1 .4 DOT P UBLICATION —Available from The Superintendent of Documents, U.S. Government Printing Office,Washington, DC 20402.
DOT/BMCS Title 40, Part 325, Subpart E—Exterior Noise Regulation for Commercial Vehicles
3. Instrumentation—The following instrumentation shall be used, where applicable, for the measurement required.
3.1 A sound level meter which satisfies the Type 1 or S1 A requirements of American National Standard Specification for Sound Level Meters, ANSI S1 .4-1 983 and S1 .4A-1 985.
3.2 As an alternative to making direct measurements using a sound level meter, a microphone or sound level meter may be used with a magnetic tape recorder and/or a graphic level recorder or other indicating instrument, providing the system meets the requirements of SAE J1 84.
3.3 A sound level calibrator, accurate to ±0.5 decibel (dB) which satisfies the requirements of ANSI S1 .40-1 984.
3.4 A windscreen may be used. The windscreen shall not affect the microphone response more than ±1 dB for frequencies of 20 to 4000 Hz or ±1 -1 /2 dB for frequencies of 4000 to 1 0 000 Hz . (See 6.1 ).
3.5 An engine-speed tachometer accurate to within ±2% of full scale.
4. Test Site—The following test site requirements shall be considered necessary to perform effective measurements for this stationary procedure.
4.1 A suitable test site shall consist of a flat open space free of large reflecting surfaces, such as parked vehicles,signboards, buildings, or hillsides, located within 30 m of either the vehicle or the microphone. See Figure 1 .