The Environmental Protection Agency (EPA) did a little recycling of its own in January by again proposing strict standards for ground-level ozone, or smog, that it first recommended in 2007.

Drafted by the Clean Air Scientific Advisory Committee (CASAC), an independent panel that provides guidance to the EPA, the standard proposed both in 2007 and in January limits the level of smog to between 0.060 and 0.070 parts per million (ppm).