4. fluorescent energy saving light bulbs, led and gaseous discharge lamps all have solid and progressive decay of the luminous flux: when the 70% of their initial flux is reached they have to be changed. a maintenance interval of 8000 hours for the fluorescent lamps, 12000 hours for the gaseous discharge lamps and 50000 hours for led, this latter in particular only if not lit at very high temperature;

5. the visual comfort, warmth and emotion that light from incandescent light bulbs is capable of generating is not yet found in other artificial light sources.

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mario nanni progettista