Indirect Sources

Updated: September 3, 2024

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Indirect sources are facilities, structures, buildings, installations, real property, roads or highways that attract or may attract mobile sources of pollution. Activities associated with an indirect source can result in emissions of air pollutants that interfere with the attainment and maintenance of NAAQS. Some examples include highways, shopping centers, stadiums, or residential developments. Some jurisdictions have implemented indirect source rules where they consider how the design, location and other factors of a development affect air pollution, allowing them to make changes onsite or offsite that will reduce that pollution.