The AQD Rules and Planning Section proposes changes to Air Quality Rules (OAC 252:100) through the Air Quality Advisory Council, which consists of nine members appointed by the Governor to represent various Oklahoma stakeholders. After proposed rule changes have been made available for public review and comment, public hearings are held, usually as part of a council meeting. If a rule change is approved by the Council, it is recommended to the Oklahoma Environmental Quality Board. Once adopted by the Board, the new rules proceed to the State Legislature and the Governor for final approval. Permanent rule changes typically become effective the following mid-September.

Air Quality Advisory Council – including upcoming council meeting dates, proposed rules, and agendas, along with a list of current council members

Rule changes from the past few years and their effective dates – updated annually

Public Participation – including a Quick Reference Guide to Public Participation in the Air Quality Rulemaking Process

EPA issues federal New Source Performance Standards (NSPS) and National Emission Standards for Hazardous Air Pollutants (NESHAPs) to regulate emissions of air pollution. AQD annually incorporates these federal rules by reference into OAC 252:100-2 and Appendix Q. Once the state rules are effective, AQD requests delegation of the individual NSPS and NESHAP subparts from EPA. Delegation is a process whereby the state assumes primary responsibility in lieu of EPA for enforcing the provisions of the rule. EPA also codifies the delegation status of the Part 63 NESHAP rules in 40 CFR Part 63, Subpart E (scroll to Oklahoma).

AQD’s current delegation status can be found here:

• NSPS Part 60
• NESHAP Part 61
• NESHAP Part 63

Oklahoma’s State Implementation Plans (SIP) lays out goals, applicable rules, procedures, and emission standards to attain and maintain compliance with the National Ambient Air Quality Standards (NAAQS) for criteria pollutants (see NAAQS Attainment Status tab).  The SIP is regularly reviewed and amended as necessary to accommodate changes in state and federal program requirements.

State Implementation Plan page – including Infrastructure SIPs (I-SIPs)

There are six criteria pollutants that act as indicators of air quality in this country: carbon monoxide, lead, ozone, nitrogen dioxide, particulate matter, and sulfur dioxide. The National Ambient Air Quality Standards (NAAQS) are the concentrations of these criteria pollutants, above which, adverse effects on human health may occur.

Areas where air pollution levels consistently stay below these standards are designated “attainment.” Areas where air pollution levels persistently exceed these standards are designated “nonattainment.” For the standards and the calculation used to determine attainment of a standard for a particular pollutant, please visit our NAAQS page. Oklahoma is currently in attainment for all six criteria pollutants.

Attainment designations for all states are listed in the Code of Federal Regulations. Oklahoma’s listings are contained in Title 40, Part 81, Section 337.  EPA also maintains a list of nonattainment areas for all six criteria pollutants on their Green Book website.

Smoke from prescribed and wildland fires release air pollutants like particulate matter and ozone precursors. Visit our Smoke Management page to learn more about reducing smoke impacts on public health and welfare.

While NSPS covers new sources, Clean Air Act (CAA) Section 111(d) allows EPA to control emissions from existing sources through emission guidelines. CAA Section 129 was added for solid waste incineration units. Emission guidelines are not direct regulations; states are required to implement and enforce these standards by developing regulations (OAC 252:100 in Oklahoma) and submitting plans to EPA.

• 40 CFR Part 62, Subpart LL – Oklahoma’s Plan for the Control of Designated Pollutants from Existing Facilities (Section 111(d) Plan)