# EPA Green Book

The EPA Green Book: which counties are designated non-attainment, or maintenance areas, for the National Ambient Air Quality Standards, per pollutant (ozone, PM2.5, PM10, sulfur dioxide, lead, carbon monoxide, nitrogen dioxide). A new major source in a non-attainment area needs emission offsets and the strictest controls, which makes permitting slower and dearer.

## Source

| Fact | Value |
| --- | --- |
| Publisher | U.S. Environmental Protection Agency |
| Product | Green Book: NAAQS non-attainment and maintenance areas by county |
| Source | [https://www.epa.gov/green-book](https://www.epa.gov/green-book) |
| Category | Hazard |
| Period | The export date of the county file |
| Refresh cadence | Monthly |
| Geographies | County, for every state and territory. A metro takes the class of its worst county, and its share of population in non-attainment counties is population-weighted. |
| Availability | Available |
| Cadastre key | `epa-green-book` |

## Licence and attribution

| Fact | Value |
| --- | --- |
| Licence | Public domain (U.S. federal government work) |
| Terms | [https://www.epa.gov/web-policies-and-procedures/epa-disclaimers](https://www.epa.gov/web-policies-and-procedures/epa-disclaimers) |
| Register status | Production approved; licence open |
| Allowed uses | `evaluation`, `internal`, `public_display`, `derived_analytics`, `redistribution`, `bulk_export`, `public_geometry`, `api` |

This source requires no credit line beyond naming the publisher. Cite it as **U.S. Environmental Protection Agency, Green Book: NAAQS non-attainment and maintenance areas by county**.

## Measures

The key is the measure's identifier in Cadastre. A measure stored for the metro itself is read as stored; **Rule from counties** is how a metro is assembled from its counties where it is not (see [Methodology](https://getcadastre.com/docs/methodology)).

| Key | Label | Unit | Rule from counties |
| --- | --- | --- | --- |
| `epa_ozone_class` | Ozone non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 marginal or moderate, 3 serious, 4 severe, 5 extreme; a county only partly inside an area counts in full) | highest value among member counties |
| `epa_ozone_nonattainment` | Population in ozone non-attainment counties (share) | share of population (0-1) in counties in ozone non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_ozone_partial` | Ozone non-attainment covers only part of the county | 0 or 1 (1 = the county's ozone class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_pm25_class` | PM2.5 non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 moderate, 3 serious; a county only partly inside an area counts in full) | highest value among member counties |
| `epa_pm25_nonattainment` | Population in PM2.5 non-attainment counties (share) | share of population (0-1) in counties in PM2.5 non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_pm25_partial` | PM2.5 non-attainment covers only part of the county | 0 or 1 (1 = the county's PM2.5 class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_pm10_class` | PM10 non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 moderate, 3 serious; a county only partly inside an area counts in full) | highest value among member counties |
| `epa_pm10_nonattainment` | Population in PM10 non-attainment counties (share) | share of population (0-1) in counties in PM10 non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_pm10_partial` | PM10 non-attainment covers only part of the county | 0 or 1 (1 = the county's PM10 class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_so2_class` | Sulfur dioxide non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 non-attainment (not classified); a county only partly inside an area counts in full) | highest value among member counties |
| `epa_so2_nonattainment` | Population in sulfur dioxide non-attainment counties (share) | share of population (0-1) in counties in sulfur dioxide non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_so2_partial` | Sulfur dioxide non-attainment covers only part of the county | 0 or 1 (1 = the county's sulfur dioxide class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_lead_class` | Lead non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 non-attainment (not classified); a county only partly inside an area counts in full) | highest value among member counties |
| `epa_lead_nonattainment` | Population in lead non-attainment counties (share) | share of population (0-1) in counties in lead non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_lead_partial` | Lead non-attainment covers only part of the county | 0 or 1 (1 = the county's lead class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_co_class` | Carbon monoxide non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 moderate or not classified, 3 serious; a county only partly inside an area counts in full) | highest value among member counties |
| `epa_co_nonattainment` | Population in carbon monoxide non-attainment counties (share) | share of population (0-1) in counties in carbon monoxide non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_co_partial` | Carbon monoxide non-attainment covers only part of the county | 0 or 1 (1 = the county's carbon monoxide class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_no2_class` | Nitrogen dioxide non-attainment class (worst county) | class (0 attainment, 1 maintenance, 2 non-attainment (not classified); a county only partly inside an area counts in full) | highest value among member counties |
| `epa_no2_nonattainment` | Population in nitrogen dioxide non-attainment counties (share) | share of population (0-1) in counties in nitrogen dioxide non-attainment; a county only partly inside an area counts in full | population-weighted county mean |
| `epa_no2_partial` | Nitrogen dioxide non-attainment covers only part of the county | 0 or 1 (1 = the county's nitrogen dioxide class rests only on areas covering part of it) | Not assembled from counties: a metro has a value only where one is stored for the metro itself |
| `epa_any_nonattainment` | Any criteria-pollutant non-attainment (metro) | 0 or 1 (1 = a county is in non-attainment for any criteria pollutant; a county only partly inside an area counts in full) | highest value among member counties |
| `epa_nonattainment_pollutants` | Pollutants in non-attainment (county with the most) | pollutants, 0-7 (in non-attainment; a county only partly inside an area counts in full) | highest value among member counties |
| `epa_worst_nonattainment_class` | Worst non-attainment class (any pollutant, worst county) | class (0 attainment, 1 maintenance, 2 marginal, moderate or unclassified non-attainment, 3 serious, 4 severe, 5 extreme; a county only partly inside an area counts in full) | highest value among member counties |

## Known gaps and caveats

- The class is a 0-5 ladder: 0 attainment, 1 maintenance, 2 marginal, moderate or unclassified non-attainment, 3 serious, 4 severe, 5 extreme.
- A county only partly inside a non-attainment area counts in full, so a metro's class is an upper bound for a site in it.
- Revoked standards are skipped.
- Connecticut replaced its eight counties with nine planning regions, which Census geography now uses; the legacy counties' designations are mapped onto the planning regions by boundary overlap, with the same upper-bound rule.
- These are county designations, not monitored air quality, not permit outcomes, and not a statement about a particular site.

## See also

- [All datasets](https://getcadastre.com/docs/datasets)
- [Rights and attribution](https://getcadastre.com/docs/rights)
- [Data freshness](https://getcadastre.com/docs/freshness)