ARTBA objected to a proposal from the U.S. Environmental Protection Agency (EPA) March 17 that would tighten the federal Clean Air Act (CAA) standard for ozone from the current 75 parts per billion (ppb) to between 65 and 70 ppb, with the option of going as low as 60 ppb.  Consequences of this proposal would impair the transportation construction community, as any of these options could increase the number of counties out of compliance with the CAA. Areas that do not comply with CAA standards can have federal highway funds withheld.  While the EPA is required by law to review the ozone standard every five years, the agency is not required to tighten it.  However, keeping the current standard does not appear to be an option EPA is willing to consider as part of their review.  Specifically, ARTBA argued there is no need to tighten federal ozone standards because current standards are working, and cited numerous federal actions that are already reducing ozone levelsRead ARTBA’s Comments.