METHODS TO CONTROL OBTRUSIVE LIGHT IN CONSIDERATION OF URBAN STRUCTURE AND OUTDOOR LIGHTING USAGE IN ASIA

摘要

As a first step to induce Asian cities to come up with measures to assess and prevent light pollution, light trespass generated due to street lightings in urban residential areas was investigated, and in order to resolve the problem, existing methods had been adapted while new methods were devised. Residential areas in Asian cities, especially those areas that had been developed long time ago, have very narrow streets. The distances between luminaires and property lines are very close, and because residential buildings are located on both sides of the street, both the forward and backward light from luminaires are sources of light trespass. In installing street lightings for an urban residential area in Asia, the new evaluation method on light trespass is one of the data of a luminaire that would enable prevention of light trespass in advance. Codes indicating both the forward and rearward distances free of light trespass is assigned. Together with other factors that either cause light trespass or affect lighting performance, installation height and distance between luminaires, these codes can be used as the rating standard for street luminaires.