US HB6387

Amends the Clean Air Act to allow states to exclude air quality monitoring data influenced by "actions to mitigate wildfire risk" (prescribed burns conducted under state-approved practices) from EPA air quality determinations, in addition to existing exceptional event exclusions

Expands the definition of "exceptional event" to include human activities intended to mirror natural events or unlikely to recur, while explicitly excluding ordinary air stagnation, meteorological inversions, and pollution from source noncompliance

Requires EPA to issue revised regulations within 18 months of enactment governing how states can petition to exclude wildfire-related air quality data from determinations affecting area designations, attainment status, and preconstruction permits

Mandates EPA conduct regional modeling and analysis when multiple states submit petitions for the same air quality event, reducing duplicative state efforts

Requires EPA to establish within 12 months a public website tracking the status of all exceptional event and wildfire mitigation petitions, updated monthly