Valutazione del rischio rumore in aziende florovivaistiche della provincia di Bergamo

Noise measurements were carried out on various machines used in green maintenance factories located in Bergamo province, to evaluate the confort level of the operators working as in private gardens and in public parks, as inside of greenhouses, comparing the results obtained with the limits provided by the relevant standards (Italian Laws 626/94 and 277/91, Machine Directive). In the years 2003 and 2004, the noise levels of about 270 machines working in 19 factories were recorded, simulating as strictly as possible the real running conditions and following the operators in their normal movements. The machines and tools were classified into 7 categories, each of them including similar types, for technical and utilization characteristics. As expected, the chainsaws are the tools showing the highest noise levels (92-102 dB(A)), together with other hand used tools. For the different combinations tractor and implement, lower levels were recorded (chipping machine, seeder, etc., 80-98 dB(A)). The electrically powered machines (air compressor, generator, etc.) showed the lowest noise (70-91 dB(A)). The Leq levels measured at the operators’ ear using the most noisy tools is remarkably over than 90 dB(A): the hearing damage is therefore a real hazard; only the electrically powered tools are relatively safe under the noise point of view. Using continuously brush cutters, chainsaws and air blowers, the green maintenance operators are much more exposed to the noise hazard in comparison with those are working inside the greenhouses, and carrying out mainly seeding, fertilizing, spraying, harvesting, etc. Due also to the poor (maintenance and use) conditions of the machinery and tools, the noise hazard level could be decreased through: - the diffusion and the careful dressing of the HPDs (Hearing Protection Devices), such as ear muffs and ear plugs; - the renewal of the machinery and tools, to be stimulated with specific economical incentives, and their careful inspection, to be carried out by the charged authorities; the frequent turning of the operators using noisy tools, providing at the same time for them suitable rest periods.