2025, expanded TAC applicability, among other revisions, to nearly any Colorado facility that emits any PTACs (as identified in the new Regulation 30: formaldehyde, benzene, hydrogen sulfide, ethylene oxide, and hexavalent chromium).
Amendments effective January 14, 2026, include updates to emission-reduction credit requirements and new definitions related to socioeconomically vulnerable communities.
The proposed emission control rules, which will fully activate the control requirements mandated by HB22‑1244, include location-based applicability criteria and revised limits for new and modified sources that are more stringent than the federal limits. For existing sources, emission thresholds are based on actual annual emissions. New provisions outline actions to take if future emissions exceed the threshold, including new reporting and retrofit options.
Through a set of related rulemakings directed by
HB22-1244, the Air Pollution Control Division of Colorado has established most of the regulatory framework for the new Priority Toxic Air Contaminants (PTAC) Program. When complete, the Program will impose toxicity-driven emission standards and reporting requirements that have no federal equivalent. Adoption of the final element, emissions control rules, is scheduled for April 2026.
The first compliance date under Program rules is June 30, 2026, when enhanced annual toxic air contaminant (TAC) reports are due for the 2025 reporting year. Amendments to Regulations 3 and 7, effective June 14,
2025, expanded TAC applicability, among other revisions, to nearly any Colorado facility that emits any PTACs (as identified in the new Regulation 30: formaldehyde, benzene, hydrogen sulfide, ethylene oxide, and hexavalent chromium).
Amendments effective January 14, 2026, include updates to emission-reduction credit requirements and new definitions related to socioeconomically vulnerable communities.
The proposed emission control rules, which will fully activate the control requirements mandated by HB22‑1244, include location-based applicability criteria and revised limits for new and modified sources that are more stringent than the federal limits. For existing sources, emission thresholds are based on actual annual emissions. New provisions outline actions to take if future emissions exceed the threshold, including new reporting and retrofit options.