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Managing Air Quality - Ongoing Evaluation of Progress

EPA, state, local, and tribal environmental program managers, as well as regulated industry and the public, want to know if air quality programs are achieving the desired results.  They want to know:

  • Are we achieving our air quality goals? 
  • Are the control programs resulting in reductions in emissions of the targeted pollutants? 
  • What are the overall costs and benefits?
  • Are sources complying with emission limits and requirements?
  • Are the number of days where air quality is unhealthy decreasing?
  • Are there improvements in health outcomes as a result of improving air quality?
  • Are we seeing reversal of ecological effects resulting from reductions in air pollution?

There are numerous ways to determine the success of the environmental programs designed to reduce pollution and achieve air quality goals.  They use the same tools employed to characterize air pollution sources, air quality, and public health and environmental impacts, including:

  • Monitored air quality concentrations, air deposition measurements, and monitored trends over multiple years;
  • Multi-year trends in emissions by source and/or jurisdiction (local, state, region, national), based on regular reporting and quantification of emissions;
  • Trends in health endpoints attributable to changes in air quality;
  • Trends in environmental degradation attributable (whole or in part) to atmospheric deposition of air pollution (e.g., lake/stream acidification, lichen surveys, fish tissue sampling);
  • Inspection and compliance reports; and
  • Benefits and costs of implementing clean air programs.

The information gained from these tools helps environmental managers determine the degree to which control programs are successful and helps them determine any changes necessary to improve effectiveness.

Examples of evaluations and reports issued by EPA are at: