The Cleveland area is one of about 50 around the country that has failed to meet ozone standards in the EPA's most recent study.
Eighty-five percent of counties across the country met the standards.
Amendments to the 1970 Clean Air Act require the EPA to set standards and rules for six air pollutants. The agency reviews them every five years and, if results dictate, it revises them. For new standards, the EPA then must figure out which areas are failing to meet them and work to bring those areas into compliance.
Ozone is one of the six, although it's slightly different than the others. It's a secondary pollutant, formed when nitrogen oxide mixes with volatile organic compounds in the presence of UV light from the sun. And, when it comes to ozone ratings, the decision is made not just on monitored data, but also air quality data, emissions, meteorology, geography and jurisdiction, because ozone forms downwind of emission sources.
The non-attainment designation for the Cleveland area includes not just Cuyahoga County, but Lorain, Summit, Medina, Portage Lake and Geauga, the latter two where there are typically higher ozone levels since they're east and downwind.
Cleveland's three-year average from 2014 to 2016 was 74 parts per billion (ppb), which was above the 70 ppb standard set by the EPA in 2015 (lowered from 75 ppb in 2008). The area is held to the highest rating in the region, which came from Lake County.
All of those counties notched higher ozone levels in this three-year period than the previous one, though the increases were small.
High levels of ozone are dangerous to older adults, those with asthma, children and people who work outdoors, and generally are great for anyone with a lung disease.
What happens next?
Since the non-attainment was "marginal," meaning Cleveland was close to meeting the standard, the area will have three years to show lowered pollution levels. That will be achieved by a state implementation plan that has to be approved by the EPA, and in our case, it will include things like e-check, stricter emissions controls for factories, different formulations for gasoline that lower emissions, as well as federally imposed regulations on power plant and tailpipe emissions. Many of those are already included in Ohio's 2008 SIP and have already reduced emissions, and will likely continue to do so over the next three years to get under the 70 ppb benchmark.