Emissions Inventory

2018 Emission Inventory Surveys Distributed,
Annual Series of Workshops Concluded

May 2019-Emissions inventory workshops to provide assistance in completing calendar year 2018 annual emissions surveys for calendar year 2018 activity have been concluded.

A new series of workshops will be announced in early 2020 for those facilities that need help in completing the 2019 reports. If you have questions regarding emissions inventories please call (602) 506-6790 or email emissionsinventory@maricopa.gov for assistance.


The Maricopa County Air Quality Department's (MCAQD) Emissions Inventory (EI) Unit collects, reviews, stores and manages stationary source air pollution emissions data for sources in Maricopa County. The EI Unit also collects emission fees from Title V sources and provides data to county, state and federal agencies.

A point source emissions inventory shows annual air pollutant emissions for one specific business location. An emissions inventory may be requested by MCAQD of any facility with an air quality permit in Maricopa County. At the beginning of each year, the EI unit distributes reporting forms and instructions to those businesses that have been requested to submit an emissions report for the prior calendar year.

Annual emissions inventories serve a number of purposes:

  • They help determine a source's compliance with its air quality permit conditions as well as Maricopa County rules and regulations.
  • They help identify pollutant sources that may need new or additional controls, and thus provide a basis for improved air pollution control strategies.
  • They also provide a means of assessing progress in achieving reductions from existing controls.
  • They provide the basis for determining annual emission fees from Title V sources.
  • Inventory data are used as input for air quality modeling to demonstrate attainment of national ambient air quality standards (NAAQS).

Page Reviewed 10 MAY 2019