Case study: Analysis of the propagation of noise generated by construction equipment

In the construction industry, workers are exposed to several risks, among them is the noise generated by construction equipment. This research had as its objective to evaluate the noise emitted by circular saws and concrete mixers, equipments usually present on construction sites, in order to propose noise control measures. For that purpose, the propagation curves (isoclines) of the sound pressure level (SPL) were measured and analyzed during the operation of three concrete mixers and three circular saws. The sound measurements were conductedwith the type 2 sound level meter, while for air temperature and wind speed a digital thermo-anemometer was used. Contour lines representing the isoclines of SPL were generated, and control measures were proposed. The results show that values of SPL above 85 dB(A) were observed at a maximal distance of 7 m from the source for concrete mixers and 16 m for circular saws. It was also confirmed that the furthest distance that the SPL is greater than 85 dB(A) depends on the number of barriers, screens and masonry walls. In obstacle-free areas, the rate of reduction of sound intensity was 1.26 dB(A) per meter for concrete mixers and 1.47 dB(A) per meter for circular saws. The SPL isoclines should be considered in planning of construction sites and organizing adequate control measures.