The following table presents the latest dates by which the national standards are to be attained. The dates reflect the information presented in New Hampshire's plan.
| Air quality control region
| SO 2
| PM 10
| NO 2
| CO
| O 3
|
|---|
| Primary
| Secondary
|
|---|
| NH portion Andoscoggin Valley Interstate AQCR 107 | a | b | a | a | a | a
|
| Central NH Intrastate AQCR 149 | a | b | a | a | a | a
|
| NH portion Merrimack Valley-Southern NH Interstate 121:
| | | | | | |
| Belknap County | a | b | a | a | a | a
|
| Sullivan County | a | b | a | a | a | a
|
| Cheshire County | a | b | a | a | a | d
|
| Portmouth-Dover-Rochester area (See 40 CFR 81.330) | a | b | a | a | a | e
|
| NH portion Boston-Lawrence-Worcester area (See 40 CFR 81.330) | a | b | a | a | a | f
|
| Manchester area (See 40 CFR 81.330) | a | b | a | a | a | c
|