A PROPOSED EXPERIMENT TO EVALUATE ENVIRONMENTAL DEPENDENCE OF THE MEASUREMENT OF NOISE FROM MEDIUM AND HEAVY DUTY TRUCKS
Increasing concern with the impact of transportation noise on communities has led to an increase in the number of motor vehicle noise regulations at all levels of government. As regulations become more widespread, the accuracy and precision of vehicle noise measurements become more critical since each uncertainty in the measurement requires a corresponding increase in the margin that manufacturers must allow between the regulated noise limit and vehicle design levels. Although considerable uniformity has been achieved by existing voluntary standards, there remain significant variations between noise measurements made at different sites or at different times on the same site. These variations are attributable to differences in the environment, including site and meterological influences. Thus, there is a need for systematic investigation of the various environmental and test site effects on noise generation, radiation and/or propagation. This report presents the findings of a feasibility study for an experiment to investigate environmental effects on truck noise emission measurements. The result of this study is a proposed experiment designed to examine the systematic and nonsystematic dependence of observed truck driveby noise on the environmental effects present during the measurement. The experiment is designed in such a manner as to permit separation of emission and propagation effects. Although it may not be feasible to determine 'correction factors' for environmental effects within the time and financial constraints of this experiment, it is fully expected that the data obtained from this experiment will reveal the magnitude of variations in the measurement and provide a broad enough information base for study of the underlying physical mechanisms.
- Prepared in cooperation with Motor Vehicle Manufacturers Association of the United States, Inc., Detroit, Mich.(PC A04/MF A01)
National Bureau of StandardsInstitute Basic Standards
Motor Vehicles Manufacturers Association320 New Center Building
Detroit, MI USA 48202
- Holmer, C I
- Kilmer, R D
- Publication Date: 1976-9
- Pagination: 68 p.
- TRT Terms: Acoustic measuring instruments; Acoustics; Data collection; Data reduction; Environmental impacts; Heavy vehicles; Noise; Noise control; Sound transmission; Test facilities; Traffic noise; Transportation; Trucks; Vehicle design
- Uncontrolled Terms: Transportation noise
- Old TRIS Terms: Acoustic measurement; Noise sound; Propagation; Truck noise
- Subject Areas: Safety and Human Factors; Transportation (General);
- Accession Number: 00146650
- Record Type: Publication
- Source Agency: National Technical Information Service
- Report/Paper Numbers: NBSIR-76-1138 Final Rpt.
- Files: TRIS
- Created Date: Feb 16 1977 12:00AM