Periodic Emission Inventory Reports

Every three years the Maricopa County Air Quality Department (MCAQD) prepares periodic emissions inventory reports for ozone and particulate matter. To access previous periodic emissions inventory reports, visit the Air Quality Records and Data Portals webpage. 

Ozone Precursors

The ozone periodic emissions inventories include emission estimates for volatile organic compounds (VOC), nitrogen oxides (NO_X) and carbon monoxide (CO), which are all precursors to ozone formation. Emissions are calculated for Maricopa County and both 8-hour ozone nonattainment areas. Annual and season-day emissions are provided for all source categories.

• 2020 Ozone Periodic Emissions Inventory
• 2017 Ozone Periodic Emissions Inventory
• 2014 Ozone Periodic Emissions Inventory
• 2011 Ozone Periodic Emissions Inventory

Particulate Matter

The particulate matter (PM) emissions inventories include emissions estimates for PM less than 10 microns in diameter (PM₁₀), PM less than 2.5 microns in diameter (PM_2.5), NO_X, sulfur oxides (SO_X), and ammonia (NH₃). Emissions are calculated for Maricopa County and the PM₁₀ nonattainment area. Annual and typical daily emissions are provided for all source categories.

• 2020 PM Periodic Emissions Inventory
• 2017 PM Periodic Emissions Inventory
• 2014 PM Periodic Emissions Inventory
• 2011 PM Periodic Emissions Inventory

Carbon Monoxide 

• 2008 CO Periodic Emissions Inventory