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Air Measuring and Monitoring Research

Air monitoringEPA is a science leader in the development and improvement of instruments, methods, techniques and other tools to measure and monitor air quality and evaluate air emissions to protect public health and the environment from air pollution. Measurement research is advancing the ability to determine the composition of sources of air pollution, conduct exposure assessments, improve monitoring capabilities and support public health research, among other applications. Research is being conducted to:

  • Develop and evaluate new and improved air measurement technologies and capabilities to enable air quality regulators and managers to effectively address air quality issues.   
  • Collect air pollution emissions data from designated sources to expand the emissions inventory in the US and build understanding of atmospheric chemistry for use in making decisions to protect air quality.   
  • Develop innovative air sensor technology and analysis tools to improve the availability and accessibility of air quality measurement technology for communities and citizen scientists.  

High quality air pollution data is needed by air regulators and managers to implement the National Ambient Air Quality Standards and develop effective preventive and mitigation strategies to protect air quality. Understanding what is in the air near sources of pollution such as industrial applications, oil and gas production facilities, coal-fired power plants and highways is critical to safeguard public health and the environment from six common air pollutants and other hazardous air pollutants regulated by EPA.

EPA is advancing air measurement technologies and capabilities to assist states, communities and tribes with air quality monitoring. EPA and state and local agencies are using the research and technology to:

  • Monitor compliance with the air quality standards
  • Conduct emissions characterization research
  • Identify effective pollution prevention and control strategies
  • Develop global emissions inventories
  • Develop the next generation regulatory and compliance strategies

The research spans a wide range of technical knowledge and capabilities including:

Next Generation Air Measurement Technologies

EPA is advancing lower cost and portable air measurement technology to enhance monitoring capabilities for complying with the National Ambient Air Quality Standards. The technology is providing mobile and stationary real-time measurement capabilities that can be used to assess air quality of common pollutants and air toxics in a specific area such as around an industrial facility, oil and gas operation, rail yard or port. Air sensor equipment can be set up individually or as a sensor network in an area to provide fenceline monitoring.

Air Quality Measurement Methods

In order to effectively monitor air pollutants to implement the National Ambient Air Quality Standards, states and tribes need state-of-the-art methods for using technology that provide accurate and reliable data. EPA researchers develop new methods and make improvements to existing methods that are used to collect data on air quality.

Air Quality Emissions Inventories Using Measurements and Models

Air quality management requires an understanding of the type of air pollutants being emitted by various sources from onroad vehicles, large industrial facilities, power plants and smaller sources such as residential heating and asphalt paving. The development of emissions inventories is critical for the states to implement accurate and effective air pollution control strategies. Complete, well-referenced and quality-assured emissions profiles of air pollution sources support EPA models used by states to demonstrate compliance with the National Ambient Air Quality Standards and are used to populate emissions databases.  

Related Resources:

Related Tools: 

  • Air Sensor Toolbox
  • Federal Reference & Federal Equivalency Methods - EPA scientists develop and evaluate Federal Reference Methods and Federal Equivalency Methods for accurately and reliably measuring six primary air pollutants in outdoor air. These methods are used by states and other organizations to assess implementation actions needed to attain National Ambient Air Quality Standards.
  • RETIGO tool -- Real Time Geospatial Data Viewer (RETIGO) is a free, web-based tool that shows air quality data that are collected while in motion (walking, biking or in a vehicle). The tool helps users overcome technical barriers to exploring air quality data. After collecting measurements, citizen scientists and other users can import their own data and explore the data on a map.
  • Remote Sensing Information Gateway (RSIG) -- RSIG offers a new way for users to get the multi-terabyte, environmental datasets they want via an interactive, Web browser-based application. A file download and parsing process that now takes months will be reduced via RSIG to minutes.
  • Traceability Protocol for Assay and Certification of Gaseous Calibration Standards -- This is used to certify calibration gases for ambient and continuous emission monitors. It specifies methods for assaying gases and establishing traceability to National Institute of Standards and Technology (NIST) reference standards. Traceability is required under EPA ambient and continuous emission monitoring regulations.
  • SmART Search -- This searchable inventory offers freely available models, tools, and databases from EPA's Office of Research and Development. 


  • Science Inventory is a searchable database of journal articles, reports and presentations primarily by the EPA's Office of Research and Development.