Regulations last checked for updates: May 19, 2024

Title 40 - Protection of Environment last revised: May 16, 2024
§ 52.621 - Classification of regions.

The Hawaii plan was evaluated on the basis of the following classifications:

Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Photochemical oxidants (hydrocarbons)
State of HawaiiIIIIIIIIIIIIII
[37 FR 10860, May 31, 1972]
authority: 42 U.S.C. 7401
cite as: 40 CFR 52.621