In July 1997, EPA issued final rules revising the preliminary and secondary NAAQS (national ambient air quality standards) for particulate matter (PM) and ozone. This was opposed by a number of organizations on grounds that D construed sections 108-109 of the Clean Air Act so loosely as to render them unconstitutional delegations of legislative power. The statute required the EPA to establish NAAQS at a level to protect the public health with an adequate margin of safety.