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Measurement of Highway-Related Noise

10. Report Documentation

This section details the information to be documented in the field measurement report. It is general enough to be applicable to all sections discussed herein. Report documentation shall include all procedures in sufficient detail such that the measurement results can be repeated. It shall include clearly stated measurement objectives, field measurement equipment and detailed field measurement procedures, a description of the noise source, the descriptors used, and detailed data analyses and results, including detailed meteorological conditions.(6,8,49) A sample computation of experimental error is also recommended. Note: A sample report has been provided in Appendix D.

10.1 Site Sketches

10.1.1 Plan View

A plan view illustrates the site as if looking down upon it from above. The plan view should include the location of the source(s), receiver(s), and any notable geographical objects, such as trees, bodies of water, hills, buildings, and signs. Relative distances of all objects should also be indicated (See Figure 18).

Aerial view of the plan. Click on image for full description

Figure 18. Sample plan view.

10.1.2 Elevation View

An elevation view illustrates the site from a viewpoint normal to the ground plane, cutting across or slicing the cross-section. It should include the relative slopes and elevations of the source, receiver, terrain, buildings, and other objects at that site for a given source-receiver pair (See Figure 19).

Cross-section view of the microphone positions in relation to an uneven terrain and the near travel lane of the road. Click on image for full description

Figure 19. Sample elevation view.

10.2 Source Description

A detailed description of the source should be provided. If applicable, this may include information regarding make, model, type, speed, etc., if an individual noise source; or volume and speed, if a fleet of vehicles.

10.3 Instrumentation Description

The manufacturer, model number, serial number, and parameter settings, including gain settings, for all instrumentation should be documented. A block diagram of the measurement and analysis systems should also be included. Calibration, frequency response, and noise floor data should all be provided.

10.4 Meteorological Data

Weather conditions should be documented at a minimum of 15-minute intervals, and whenever substantial changes in conditions are noted. These conditions include wind speed, wind direction, temperature, humidity, cloud cover, and time-of-day when these data were measured.

10.5 Ground Surface Characterization

The ground characteristics for both the sources and receivers should also be documented, e.g., hard or soft ground.

10.6 Barrier Characteristics

For barrier insertion loss measurements, the following barrier characteristics need to be documented: barrier height, length, location, material, Noise Reduction Coefficient, Sound Transmission Class, and tilt angle (if applicable).

10.7 Measurement Procedures

All field measurement procedures should be documented. These procedures should be detailed such that the measurement results are able to be repeated by other individuals.

10.8 Acoustical Data

Data acquired from field measurements and analyses, as well as the procedures used, should be documented fully. Also to be recorded are all adjustments applied to the data due to calibration drift, ambient influences, and instrumentation non-linearities.

10.9 Incidental Observations and Conclusions

A discussion of any unforeseen events during the measurements should be included. Any situations that suggest modifications to the experiment for improved results should be documented. Any relevant subjective judgments or interpretations may appear in this section of the measurement report.

Updated: 7/6/2011
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