1.   These laws are meant to produce cleaner air.

2.   An outcry for cleaner air.

3.   And the goal of cleaner air is also rarely met, according to several analyses.

4.   And though specific strategies may warrant discussion, there will always be unanimity on cleaner air.

5.   And the tailpipes you replaced probably add up to a lot cleaner air than we get by increasing the stack effluent.

6.   Another round of hard-hitting political advertisements will begin airing in Bangor and Portland this weekend, focusing on a controversial proposal to promote cleaner air.

7.   And, install an electronic air cleaner or filter in the furnace to take the place of the fiberglass filters there now.

8.   And, she said, a national low-emission vehicle would make for cleaner air in places like Nebraska.

9.   Another round of hard-hitting political advertisements will begin airing in Harrisburg this weekend, focusing on a controversial proposal to promote cleaner air.

10.   Because of a generation of bipartisan effort, we have cleaner air and water.