40 CFR 52.1521 - Classification of regions.

Regulations most recently checked for updates: Aug 27, 2025

§ 52.1521 - Classification of regions.

The New Hampshire plan was evaluated on the basis of the following classifications:

Air quality control region	Pollutant
Air quality control region	Particulate matter	Sulfur oxides	Nitrogen dioxide	Carbon monoxide	Ozone
Androscoggin Valley Interstate	IA	III	III	III	III
Central New Hampshire Intrastate	III	III	III	III	III
Merrimack Valley—Southern New Hampshire Interstate	I	III	III	III	I

[37 FR 10879, May 31, 1972, as amended at 45 FR 24876, Apr. 11, 1980; 80 FR 78141, Dec. 16, 2015; 81 FR 44554, July 8, 2016]