Air quality reference
Greenfield Town, MA
Greenfield Town, MA has a published AQI value of 23, categorized as Good, for 2026-03-27T00:00:00+00:00. The defining parameter is PM2.5, based on 1 monitoring sites. AQI is a communication index rather than a direct pollutant concentration, and values from different dates, averaging periods or providers should not be treated as interchangeable. This profile provides measurement context and same-category links but does not provide individualized medical advice.
Key facts
- Location
- Greenfield Town, MA
- Air quality index
- 23
- Category
- Good
- Defining parameter
- PM2.5
- Sites reporting
- 1
- Measured at
- 2026-03-27T00:00:00+00:00
- Measurement context
- Daily AQI summary from U.S. EPA AirData; values are not direct pollutant concentrations
Historical air-quality context
Published EPA annual CBSA indicators
Annual AQI summaries are shown independently from pollutant concentrations. Current-year values are provisional because reporting is incomplete and can be revised.
Annual indicator
Days with published AQI
64.00 days2026
EPA annual CBSA summary field: Days with AQI. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 64.00 days | provisional-current-year | — |
| 2025 | 364.00 days | — | — |
| 2024 | 365.00 days | — | — |
| 2023 | 365.00 days | — | — |
| 2022 | 365.00 days | — | — |
| 2021 | 365.00 days | — | — |
| 2020 | 365.00 days | — | — |
| 2019 | 364.00 days | — | — |
| 2018 | 365.00 days | — | — |
| 2017 | 365.00 days | — | — |
| 2016 | 366.00 days | — | — |
| 2015 | 365.00 days | — | — |
| 2014 | 338.00 days | — | — |
| 1980 | 73.00 days | — | — |
Annual indicator
Good AQI days
37.00 days2026
EPA annual CBSA summary field: Good Days. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 37.00 days | provisional-current-year | — |
| 2025 | 280.00 days | — | — |
| 2024 | 296.00 days | — | — |
| 2023 | 246.00 days | — | — |
| 2022 | 271.00 days | — | — |
| 2021 | 228.00 days | — | — |
| 2020 | 246.00 days | — | — |
| 2019 | 281.00 days | — | — |
| 2018 | 289.00 days | — | — |
| 2017 | 300.00 days | — | — |
| 2016 | 296.00 days | — | — |
| 2015 | 233.00 days | — | — |
| 2014 | 198.00 days | — | — |
| 1980 | 47.00 days | — | — |
Annual indicator
Hazardous AQI days
0.00 days2026
EPA annual CBSA summary field: Hazardous Days. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 0.00 days | provisional-current-year | — |
| 2025 | 0.00 days | — | — |
| 2024 | 0.00 days | — | — |
| 2023 | 0.00 days | — | — |
| 2022 | 0.00 days | — | — |
| 2021 | 0.00 days | — | — |
| 2020 | 0.00 days | — | — |
| 2019 | 0.00 days | — | — |
| 2018 | 0.00 days | — | — |
| 2017 | 0.00 days | — | — |
| 2016 | 0.00 days | — | — |
| 2015 | 0.00 days | — | — |
| 2014 | 0.00 days | — | — |
| 1980 | 0.00 days | — | — |
Annual indicator
Maximum daily AQI
77.00 AQI index2026
EPA annual CBSA summary field: Max AQI. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | AQI index | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 77.00 AQI index | provisional-current-year | — |
| 2025 | 114.00 AQI index | — | — |
| 2024 | 94.00 AQI index | — | — |
| 2023 | 154.00 AQI index | — | — |
| 2022 | 108.00 AQI index | — | — |
| 2021 | 99.00 AQI index | — | — |
| 2020 | 96.00 AQI index | — | — |
| 2019 | 89.00 AQI index | — | — |
| 2018 | 100.00 AQI index | — | — |
| 2017 | 90.00 AQI index | — | — |
| 2016 | 115.00 AQI index | — | — |
| 2015 | 100.00 AQI index | — | — |
| 2014 | 90.00 AQI index | — | — |
| 1980 | 179.00 AQI index | — | — |
Annual indicator
Median daily AQI
47.00 AQI index2026
EPA annual CBSA summary field: Median AQI. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | AQI index | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 47.00 AQI index | provisional-current-year | — |
| 2025 | 38.00 AQI index | — | — |
| 2024 | 36.00 AQI index | — | — |
| 2023 | 43.00 AQI index | — | — |
| 2022 | 40.00 AQI index | — | — |
| 2021 | 44.00 AQI index | — | — |
| 2020 | 43.00 AQI index | — | — |
| 2019 | 40.00 AQI index | — | — |
| 2018 | 38.00 AQI index | — | — |
| 2017 | 37.00 AQI index | — | — |
| 2016 | 38.00 AQI index | — | — |
| 2015 | 44.00 AQI index | — | — |
| 2014 | 46.00 AQI index | — | — |
| 1980 | 41.00 AQI index | — | — |
Annual indicator
Moderate AQI days
27.00 days2026
EPA annual CBSA summary field: Moderate Days. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 27.00 days | provisional-current-year | — |
| 2025 | 81.00 days | — | — |
| 2024 | 69.00 days | — | — |
| 2023 | 113.00 days | — | — |
| 2022 | 93.00 days | — | — |
| 2021 | 137.00 days | — | — |
| 2020 | 119.00 days | — | — |
| 2019 | 83.00 days | — | — |
| 2018 | 76.00 days | — | — |
| 2017 | 65.00 days | — | — |
| 2016 | 67.00 days | — | — |
| 2015 | 132.00 days | — | — |
| 2014 | 140.00 days | — | — |
| 1980 | 14.00 days | — | — |
Annual indicator
90th percentile daily AQI
58.00 AQI index2026
EPA annual CBSA summary field: 90th Percentile AQI. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | AQI index | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 58.00 AQI index | provisional-current-year | — |
| 2025 | 59.00 AQI index | — | — |
| 2024 | 56.00 AQI index | — | — |
| 2023 | 61.00 AQI index | — | — |
| 2022 | 59.00 AQI index | — | — |
| 2021 | 60.00 AQI index | — | — |
| 2020 | 60.00 AQI index | — | — |
| 2019 | 56.00 AQI index | — | — |
| 2018 | 57.00 AQI index | — | — |
| 2017 | 55.00 AQI index | — | — |
| 2016 | 57.00 AQI index | — | — |
| 2015 | 64.00 AQI index | — | — |
| 2014 | 64.00 AQI index | — | — |
| 1980 | 119.00 AQI index | — | — |
Annual indicator
Unhealthy AQI days
0.00 days2026
EPA annual CBSA summary field: Unhealthy Days. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 0.00 days | provisional-current-year | — |
| 2025 | 0.00 days | — | — |
| 2024 | 0.00 days | — | — |
| 2023 | 1.00 days | — | — |
| 2022 | 0.00 days | — | — |
| 2021 | 0.00 days | — | — |
| 2020 | 0.00 days | — | — |
| 2019 | 0.00 days | — | — |
| 2018 | 0.00 days | — | — |
| 2017 | 0.00 days | — | — |
| 2016 | 0.00 days | — | — |
| 2015 | 0.00 days | — | — |
| 2014 | 0.00 days | — | — |
| 1980 | 5.00 days | — | — |
Annual indicator
Unhealthy for sensitive groups days
0.00 days2026
EPA annual CBSA summary field: Unhealthy for Sensitive Groups Days. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 0.00 days | provisional-current-year | — |
| 2025 | 3.00 days | — | — |
| 2024 | 0.00 days | — | — |
| 2023 | 5.00 days | — | — |
| 2022 | 1.00 days | — | — |
| 2021 | 0.00 days | — | — |
| 2020 | 0.00 days | — | — |
| 2019 | 0.00 days | — | — |
| 2018 | 0.00 days | — | — |
| 2017 | 0.00 days | — | — |
| 2016 | 3.00 days | — | — |
| 2015 | 0.00 days | — | — |
| 2014 | 0.00 days | — | — |
| 1980 | 7.00 days | — | — |
Annual indicator
Very unhealthy AQI days
0.00 days2026
EPA annual CBSA summary field: Very Unhealthy Days. Current-year values are provisional because reporting is incomplete and can be revised. Values retain the source period and unit.
View source data
| Period | days | Source flag | Confidentiality |
|---|---|---|---|
| 2026 | 0.00 days | provisional-current-year | — |
| 2025 | 0.00 days | — | — |
| 2024 | 0.00 days | — | — |
| 2023 | 0.00 days | — | — |
| 2022 | 0.00 days | — | — |
| 2021 | 0.00 days | — | — |
| 2020 | 0.00 days | — | — |
| 2019 | 0.00 days | — | — |
| 2018 | 0.00 days | — | — |
| 2017 | 0.00 days | — | — |
| 2016 | 0.00 days | — | — |
| 2015 | 0.00 days | — | — |
| 2014 | 0.00 days | — | — |
| 1980 | 0.00 days | — | — |
Field-level provenance
Sources for this profile
Dates and licenses apply to the specific facts and series supplied by each source.
U.S. EPA AirData
- Applicable date
- 2026-03-27
- Dataset version
- 10350f77cf0f
- License
- U.S. federal factual data; verify third-party fields
- Attribution
- U.S. Environmental Protection Agency
U.S. EPA AirData
- Applicable date
- 2026-07-30
- Dataset version
- annual-aqi-by-cbsa-v1
- License
- U.S. federal factual data; verify third-party fields
- Attribution
- U.S. Environmental Protection Agency
DataOfWorld deterministic air-quality profile template
- Applicable date
- 2026-03-27
- Dataset version
- air-quality-profile-v1
- License
- Original DataOfWorld text
- Attribution
- DataOfWorld
Reference data can change. Verify consequential decisions against the original source.