Air Plan Approval; Arizona; Interstate Transport Requirements for the 2012 Fine Particulate Matter National Ambient Air Quality Standards

What it does

The Clean Air Act (CAA) requires each state implementation plan (SIP) to contain adequate provisions prohibiting emissions that will significantly contribute to nonattainment or interfere with maintenance of air quality in other states. The State of Arizona submitted SIP revisions to the Environmental Protection Agency (EPA) to address these requirements for the 2012 fine particulate matter (PM<INF>2.5</INF>) national ambient air quality standards (NAAQS). The EPA is finalizing approval of Arizona's SIP submission as meeting the requirement that the Arizona SIP contains adequate provisions to prohibit emissions activity, within the State, from emitting air pollutants in amounts that will significantly contribute to nonattainment or interfere with maintenance of the 2012 PM<INF>2.5</INF> NAAQS in any other state.

The Environmental Protection Agency's summary, as published in the Federal Register.

What changed in the regulation

1 part of Title 40 of the Code of Federal Regulations:

40 CFR 52

Wording on eCFR: the day before it took effect and from the day it took effect (first part listed).

Compared with

The Environmental Protection Agency has published 245 final rules in 2026 so far, compared with 263 in all of 2025.

Counted by the Tribune from Federal Register records since Jan. 1, 2025.

What happens next and when

This rule is effective May 18, 2026.

The agency's dates, word for word.

Check it yourself

• The document in the Federal Register
• Docket EPA-R09-OAR-2025-0191 on Regulations.gov
• Title 40 on eCFR

The record as published

Source: the Federal Register (public domain). The document in the Federal Register