Air Quality Index (AQI)

Back to all collections

Summary

The U.S. Air Quality Index (AQI) is EPA's tool for communicating about outdoor air quality and health. The AQI includes six color-coded categories, each corresponding to a range of index values. The higher the AQI value, the greater the level of air pollution and the greater the health concern.

Agency EPA
Data Checkup

Historical Data Availability

No Known Issue

Future Data Availability

No Known Issue

Data Quality

High Risk
In March 2025, AirNow shut down its webpage reporting air quality data from U.S. embassies and consulates worldwide, ending public access to approximately 17 years of data from about 80 diplomatic posts. Although the underlying sensors reportedly continue to collect data, the data are no longer published on AirNow.gov.

Statutory Context

No Known Issue
The Air Quality Index is statutorily mandated. Under Section 319 of the Clean Air Act, EPA is required to establish a nationally uniform, color-coded index for reporting daily air quality to the public.

Staffing and Funding

Moderate Risk
From FY2024 to FY2027, EPA lost more than 25% of its staff. The FY2027 President's Budget for EPA proposes decreasing funding for EPA by more than 50%, and the FY2027 House Committee Appropriations bill proposes a 20% funding reduction.

Policy

High Risk
In 2025, EPA initiated deregulation efforts, focusing on reversing climate policies, cutting scientific research, and reducing enforcement to prioritize economic growth over strict environmental compliance. AirNow also suspended global air monitoring at 70+ cities that alerted U.S. citizens in those regions to air quality.
Last updated: 2026-08-13

Details

OMB Control Number 2060-0084
Authorizing Statutes 42 USC 7401 et seq
Related ICRs
Reference Number Title Agency Status Request Type
202307-2060-004 Ambient Air Quality Surveillance (Renewal) EPA/OAR Active
Revision of a currently approved collection
Subscribe