Czechia on the way to sustainable lighting 


Jan Hollan (N. Copernicus Observatory and Planetarium in Brno,
Kraví hora 2, CZ-616 00 Brno, Czechia) 


In the course of one year the light pollution became illegal in
Czechia, from the very idea to include it into the Clean Air Act
till it became valid June 1, 2002.

The idea and the key work to make it true is due to Stanislav
Fischer, an astronomer who had been a member of the House of
Representatives for many years. The background info, the proposed
wording of the law and endorsement letters have been submitted to
the House by the Czech Astronomical Society.

Astronomers acted as environmentalists with the best
understanding of the broad problem, thanks to their natural
interest in the protection of the night. Environmentalists from
other professions begin now to be interested as well.

For each pilot project to make the outdoor lighting sustainable
in a small area at least, a fully devoted person is necessary. I
hope some will emerge within national parks or municipalities, in
addition to some observatories.

As the problem is very new for most of the Czech population, the
issuing of concrete measures to start a pronounced decline of
light pollution has been postponed by the Ministry of
Environment. The current discussion gave no arguments against a
Lombardy-like measures.

At the moment, obeying the law cannot be enforced. This is maybe
not bad, as a voluntary adherence to the law helps to raise the
public awareness and responsibility.

One issue which needs to be made clear, is the necessity of the
ban of direct emissions above horizon for all strong light sources. 
Especially the almost horizontal light is harmful, much more than the 
light going steep upwards. Most of the almost horizontal light comes 
from the luminaires themselves, not from the lit terrain. Such light 
contributes most to the unwanted sky luminance and to the ugly appearance 
of the landscape, kills birds and insects, reduces safety of 
transport, disturbs sleep of substantial fraction of population. (An 
author's programme ies2tab helps to get a quick overview which 
luminaires are OK and which are not.)

Another issue is the involvement of local residents into lighting 
projects. When a building or a monument is to be lit, all the people 
which would then get more light into their windows should be asked, 
if their bedrooms are not affected. If yes, the project is to be 
either abandoned or modified in such a way, that the illumination of 
bedrooms does not rise -- in any case, after the curfew. 

Some examples from Brno, both good and bad, are presented. 

(for more info, see http://www.astro.cz/darksky)