[Darksky]letter to the Minister

[Fabio Falchi]

Hon. Minister of Environment Libor Ambrozek ,

knowing that Czech Republic is working on the light pollution part of the
Clean Air Act, as a light pollution and lighting expert, I'd like to give my
contribute to your effort.
In the last few years has been scientifically demonstrated that light
pollution is produced primarily by the direct emissions from the luminaries
and secondarily from the light reflected by the lighted surfaces (i.e.
streets, squares, buildings and so on).
Of the light escaping directly above the horizon from the luminaries, the
most polluting is the one emitted at low angles above the horizon plane,
such as that produced by the semi cut-off luminaries. These facts implies
that to control light pollution and its consequences on our ecosystem a law
should:
- impose the exclusive use of  Fully Shielded or Full Cut-Off luminaries for
all type of illuminations (streets, squares, buildings, sporting facilities
etc.)
- impose an upper level to the luminance of the lighted surfaces (a common
value chosen by the most recent laws is 1 candela/square meter)
- impose the use of the less pollution lamps (basing the judgement on the
control of their emission spectra).
All these prescription are used with success in the most developed Italian
region: Lombardy. In that region (nearly 10 million inhabitants) all new
lights must follow the technical criteria above. Exceptions are given only
for historical buildings and monuments (that must follow other light
pollution requirements) and for very small lamps (less than 1500 lumens).
The experience maturated in Lombardy demonstrates that the Fully Shielded
lights can cover all types of lighting needs.
All Italian manufacturer now has in their catalogs luminaries that meet the
Lombardy's Law, being in that way on the forefront of the world market.
In order that also Czech manufacturers follow the market lead a law that
seriously combat light pollution should be approved. The only way to do that
not limiting the number of new lights is to follow, at least, the three
points above.
I hope I hasn't been tedious.
With my Best Regards,
Fabio Falchi
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FABIO FALCHI
Istituto di Scienza e Tecnologia dell'Inquinamento Luminoso - ISTIL
Light Pollution Science and Technology Institute
e-mail: falchiAlightpollution...
web: http://www.istil.it
     http://www.inquinamentoluminoso.it
     http://www.lightpollution.it/dmsp/
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