**SNIP** Under the new law, the interior lights of nonresidential buildings will have to be turned off an hour after the last worker leaves, and lights on building facades and in shop windows will have to be extinguished by 1 a.m. Ms. Batho also presented the decree as a matter of public health. Artificial lighting can damage sleep patterns, she said, and also “cause significant disruptions on ecosystems by changing communication between species, migrations, reproduction cycles or even the prey-predator relationships.”