One of the most complex subjects in lighting design, is related to restaurants, docks and other recreation areas which provide service in outdoor landscapes. Lighting design of these spaces is a real paradox.
One of the main consequences of inappropriate design of lighting in these cases, is accumulation of insects such as mosquitoes around the lights which threats the family hopes to spend a pleasurable evening outdoors …
In general, the light-sensitive insects are divided into three categories which are photo-negative, photo-positive and photo-tactic. Photo-positive insects, which encompasses the majority of known insects, are attracted to ultraviolet light. Conversely, photo-negative insects, which live in the soil, escape from the light.
Finally, photo-tactic insects are including the insects, such as bees, which absorb to light and use it for purposes such as generating thermal energy and navigation.
Studies which is conducted on the lights shows that mercury vapor lamp is the most attractive one for the insects. After it, fluorescent lamps (including CFLs), incandescent lamp, sodium vapor lamp and LED lamps are in the next level of attraction respectively.
So, in such cases, it is better to use the LED lights (despite the relatively high-price). Because , in addition to their lower ultraviolet radiation and so very little attraction to insects , they have a better CRI in comparison with sodium vapor lamps. Furthermore, in the long term, LED lights, due to lower power consumption, offset a part of high cost of initial investment.