On October 1, 2015, the United States Environmental Protection Agency (“EPA”) adopted stricter regulation on ozone emissions that will fall heavily on California, and most particularly on the transportation sector, including airlines.  The new standard strengthens limits on ground level ozone to 70 parts per billion (“PPB”), down from 75 PPB adopted in 2008.  The EPA’s action arises from the mandate of the Clean Air Act (“CAA”), from which the EPA derives its regulatory powers, 42 U.S.C. § 7409(a)(1), and which requires that pollution levels be set so as to protect public health with an “adequate margin of safety.  42 U.S.C. § 7409(b).  

The change has inspired significant controversy throughout the country, but most particularly in Southern California which purportedly has the nation’s worst air quality and has already failed to meet previous ozone standards.  The issues arise out of the likelihood that the new standards will require steep emissions cuts falling most heavily on the transportation sector including trains, trucks, ships and, not least, aircraft.  

On the one hand, representatives of manufacturers and of the transportation industry such as the National Association of Manufacturers take the position that the higher level of restrictions “inflict pain on companies that build things in America.”  Supporting this position is the reality that the new ozone limits cannot be attained in Southern California without tougher emissions standards for, among other things, aircraft engines.  The standards for aircraft engines are, however, solely within the combined jurisdiction of the Federal Aviation Administration (“FAA”) and EPA, 42 U.S.C. § 7571(a)(2)(B)(i), and, thus, are outside the jurisdiction of local agencies such as the Southern California Air Quality Management District (“SCAQMD”).  Nor is the EPA tasked with considering costs when establishing ozone and other limits, but can factor in costs which determining the way in which states carry out the rules. 

On the other side of the argument, environmentalists, who were hoping for an even more restrictive standard of 60 PPB, point out that, during the almost five decades that ozone limits have been in effect, air pollution has declined by 70% while gross domestic product has increased threefold.
 
The bottom line is that, ultimately, the responsibility for compliance by aircraft engine manufacturers belongs jointly to the FAA and EPA, but the responsibility for the as yet uncalculated costs, as well as the timeframes required for compliance, belong solely to the manufacturers.  The verdict is still out as to the potential cost to the public health if the prescribed limits were not to be implemented.