Data provided here are uploaded in near real-time and represent raw measurements reported by the commercially manufactured sensors. Air quality sensors use different measurement technologies than US EPA approved Reference/Regulatory Monitors and may occasionally report questionable data, especially under certain weather conditions such as fog or snow.

To learn more about US EPA guidelines about using sensors and understanding data from sensors please reference the US EPA Air Sensor Toolbox: https://www.epa.gov/air-sensor-toolbox.

Data are provided for general informational purposes only.

The U.S. EPA AirNow program (www.AirNow.gov) protects public health by providing forecast and real-time observed air quality information across the United States, Canada, and Mexico. AirNow receives real-time air quality observations from over 2,000 monitoring stations and collects forecasts for more than 300 cities.

All data provided by AirNow API and AirNow Gateway are made possible by the efforts of more than 120 local, state, tribal, provincial, and federal government agencies (Participating Agencies). These data are not fully verified or validated and should be considered preliminary and subject to change.

Data and information reported to AirNow are for the express purpose of reporting and forecasting the AQI. As such, they should not be used to formulate or support regulation, trends, guidance, or any other government or public decision making. Official regulatory air quality data must be obtained from EPA's Air Quality System (AQS or AirData).

GreenRoots

Data provided here are uploaded in near real-time and represent raw measurements reported by two types of commercially manufactured air quality sensors. Symbols with colored fill show air quality based solely on particle measurements. Symbols with grayscale fill provide a measure of ultrafine particles.

Air quality sensors use different measurement technologies than US EPA approved Reference/Regulatory Monitors and may occasionally report questionable data, especially under certain weather conditions such as fog or snow.

To learn more about US EPA guidelines about using sensors and understanding data from sensors please reference the US EPA Air Sensor Toolbox: https://www.epa.gov/air-sensor-toolbox. To learn more about the ultrafine particle sensor: https://docs.quant-aq.com/hardware/modulair-ufp

Data are provided for general informational purposes only.

Revere

Data provided here are uploaded in near real-time and represent raw measurements reported by two types of commercially manufactured air quality sensors. Symbols with colored fill show air quality based solely on particle measurements. Symbols with grayscale fill provide a measure of ultrafine particles.

Air quality sensors use different measurement technologies than US EPA approved Reference/Regulatory Monitors and may occasionally report questionable data, especially under certain weather conditions such as fog or snow.

To learn more about US EPA guidelines about using sensors and understanding data from sensors please reference the US EPA Air Sensor Toolbox: https://www.epa.gov/air-sensor-toolbox. To learn more about the ultrafine particle sensor: https://docs.quant-aq.com/hardware/modulair-ufp

Data are provided for general informational purposes only.

NOAH East Boston Air Quality Project

Data provided here are uploaded in near real-time and represent raw measurements reported by two types of commercially manufactured air quality sensors. Symbols with colored fill show air quality based solely on particle measurements. Symbols with grayscale fill provide a measure of ultrafine particles.

Air quality sensors use different measurement technologies than US EPA approved Reference/Regulatory Monitors and may occasionally report questionable data, especially under certain weather conditions such as fog or snow.

To learn more about US EPA guidelines about using sensors and understanding data from sensors please reference the US EPA Air Sensor Toolbox: https://www.epa.gov/air-sensor-toolbox. To learn more about the ultrafine particle sensor: https://docs.quant-aq.com/hardware/modulair-ufp

Data are provided for general informational purposes only.

The National Emissions Inventory (NEI) is a comprehensive and detailed estimate of air emissions of criteria pollutants, criteria precursors, and hazardous air pollutants from air emissions sources. The NEI is released every three years based primarily upon data provided by State, Local, and Tribal air agencies for sources in their jurisdictions and supplemented by data developed by the US EPA.

NEI point sources include emissions estimates for larger sources that are located at a fixed, stationary location. Point sources in the NEI include large industrial facilities and electric power plants, airports, and smaller industrial, non-industrial and commercial facilities.

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