Draft 2021 Network Plan
Each year, MassDEP is required to submit an Ambient Air Monitoring Network Plan to the U.S. Environmental Protection Agency (EPA) for review and approval.
MassDEP operates a network of 23 ambient air monitoring stations in 19 communities located across the Commonwealth. The Network Plan reviews the air monitoring network to ensure that it meets EPA's monitoring requirements, describes which pollutants and other parameters MassDEP measures, and describes recent and planned changes to the monitoring network.
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The agency held a 30-day public comment period on its Draft 2021 Network Plan, ending on July 15, 2021. If you have questions, please direct them to: sean.m.dunn@mass.gov
See Additional Resources below for the final Network Plan and attachments.
Additional Resources for
About the Monitoring Network & Plan
The Massachusetts Department of Environmental Protection (MassDEP) operates a network of 23 ambient air quality monitoring stations at locations across the state. The Wampanoag Tribe of Gay Head (Aquinnah) operates an ozone monitoring station on Martha's Vineyard. Each year, MassDEP is required to submit an Annual Ambient Air Quality Monitoring Network Plan to the U.S. Environmental Protection Agency (EPA). This document and its attachments are subject to a 30-day public comment period before MassDEP submits them to EPA for review and approval.
The annual network plan describes to EPA which pollutants and other parameters MassDEP measures at its various ambient air monitoring sites and why they are measured at those specific locations. It also describes changes in the network - including new and closed locations, and new and discontinued measurements at existing locations - since the last network plan, as well as proposed changes in the network over the next 18 months.
MassDEP also must conduct an assessment of the Massachusetts Ambient Air Quality Monitoring Network every five years to determine whether it meets the objectives defined in EPA regulations.
Air Monitoring Network Sites Map & Table
Zoom in ( + ) and click on the icons to learn about each monitoring station site across Massachusetts.
Legend of Parameter Acronyms
| O3 | Ozone |
| CO | Carbon Monoxide |
| SO2 | Sulfur Dioxide |
| NOx | Nitric Oxide, including Nitrogen Dioxide |
| NOy | Total Reactive Oxides of Nitrogen |
| MET | Meteorological Parameters |
| PM10 | Particulate Matter (10 microns & smaller) |
| PM2.5 | Fine Particles (2.5 microns & smaller) |
| VOC | Volatile Organic Compounds |
| TOXICS | Toxic Air Pollutants including Carbonyls (Aldehydes), Metals & VOCs |
| BC | Black Carbon |
| SPEC | Speciated Fine Particles |
| IMPROVE | Visibility PM Speciation |