Experience Predicting Construction-Site Noise

The practical aspects of predicting construction-site noise are examined: the implementation of the prediction process, including the use of suitable source-noise emission measurement standards, the identification of propagation factors, and the assumption of meteorological conditions. The application of a prediction procedure is compared with field measurements to verify accuracy and to establish appropriate design safety margins. To estimate the site sound levels from one or more noise sources, sound attenuation was considered due to four mechanisms—spreading, atmospheric absorption, ground reflections (“ground interaction”), and barrier shielding. Noise-source emissions were measured essentially at maximum noise-generation conditions for the equipment, based on the test procedures of both the Society of Automotive Engineers and the American National Standards Institute. Prediction accuracy was verified for eight sites with 19 total locations and conditions. When observed primary-machine sound levels were compared with the predictions, the mean error was 3 dB(A). For group equipment operations and measurement-period sound levels, which are subject to source operating condition variation and mobile-equipment movement, the mean equivalent sound-level overprediction was approximately 6 dB(A).