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Street lighting plays a crucial role in a city’s night landscape and in urban traffic management, influencing users’ comfort and safety. To contain costs of public street lighting systems and to avoid energy waste, illuminance levels on road surfaces must be adequate to fit actual traffic volumes, as prescribed by regulations. This is true not only for motorized roads but also for sidewalks, paths, and pedestrian areas. Regulations in force establish a relationship between road traffic volumes and minimum illuminance levels through the lighting classes selection procedure. Lighting classes selection is based on various para meters among which traffic volume is the most difficult to evaluate because traffic volumes are generally estimated or measured by a traffic observation campaign. In this paper, an alternative method for classes association which is based on a space syntax approach, is described. The method was applied to the case study town of Pontedera (Italy) for the analysis of the pedestrian and motorized traffic and it shows a good correlation between measured and estimated traffic volumes, demonstrating how the methodology, with a precise and quick estimation of traffic volumes, can help lead to a suitable design of the lighting infrastructure, aiming to reduce energy waste and to avoid oversized lighting systems.

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Solar Ultra-Violet (UV) radiation has positive and negative effects on human body tissues. Small doses of solar UV radiation are needed by the human skin for the activation of the vitamin D production. Overexposure to solar UV radiation can produce acute and long-term negative effects, such as sunburns and, in the worst cases, cataracts and skin cancers. For this reason, knowing the amount of UV doses received by people is essential to evaluate their risk to UV overexposure and to evaluate the adequate countermeasure to avoid the negative effects. The original contribution of the present study consists in having searched, collected, adapted and processed a series of technical information and analytical relations, developing an algorithm suitable for the calculation of the erythemal UV dose on sloped surfaces exposed to solar radiation, which at the moment is not present in the scientific literature. The results obtained by the algorithm have been compared to the results of a field measurements campaign, carried out in three different Italian sites. Results comparison indicated that measured and calculated values show a sufficient level of agreement, with a mean absolute error equal to 20%.

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