For previous years see 2020, 2019, 2018, 2017, 2016 or 2015-1998.
Ozone 8 hour Averages Although the federal and state 8-hour average ozone standards are both set at 70 ppb, recorded levels for the state standard are rounded to the nearest whole number, while levels for the federal standard are truncated to the nearest whole number. For example, a value of 71.6 would be rounded to 72 for the state standard and truncated to 71 for the federal standard.
Particulate Matter PM10 is calculated different when being compared to the state standard versus the federal standard. The PM10 state 24 hour value is a rounded average of the monitors 24 hourly readings in a day using local ambient temperature and pressure conditions. The PM10 federal 24 hour value is a truncated average of the monitors 24 hourly readings in a day using standardized temperature and pressure conditions. This difference results in slightly different 24 hour averages for each monitoring station on a given day.