Maine DEP Issues an Air Quality Alert in Response to Canadian Smoke Plume

September 6, 2023

Particle pollution concentrations are expected to reach "Unhealthy for Sensitive Groups" (USG) level Wednesday September 6, 2023, according to the Maine Department of Environmental Protection (DEP). A dense ground-level plume of smoke from fires in Canada moved into Maine last night. In the Northern region particle pollution levels are currently continuing in the USG range this morning and will likely remain at that level for at least the morning hours. For the day, the 24-hour average is expected to be in the USG range for the Northern region. For the remainder of the state, the 24-hour average is expected to be Moderate with only a few hours above Moderate. At elevated particle pollution levels, children, healthy adults who exert themselves, and individuals suffering from a respiratory disease such as asthma, bronchitis or COPD can experience reduced lung function and irritation. When this happens, individuals may notice a shortness of breath, coughing, throat irritation, and/or experience an uncomfortable sensation in their chest. Additionally, those with a heart disease should also follow these recommendations.

Some actions you can take to protect your health during periods of unhealthy air quality include:

  • Avoid strenuous outdoor activity.

  • If you are exposed to heavy smoke or have health concerns that might be worsened by smoke, consider wearing a N95 or KN95 mask. If you do not have one on hand, any well-fitting mask would likely help reduce some of the particles potentially inhaled into the lungs.

  • If you are indoors, close windows and circulate indoor air with a fan or air conditioner.

  • The Maine CDC Asthma Prevention and Control Program has asthma information available at their web site:

  • For more information on asthma control visit EPA's Web site to find information about asthma triggers and lessons on asthma management.

  • Health information for smoke impacted areas: In addition to those in a sensitive group, sports coaches, elder care workers, nurses and others who are responsible for the welfare of people impacted by poor air quality are urged to use one of the listed tools to follow the Air Quality Forecast:

"Wildfires and Air Quality" online resource set up by the Mills Administration with guidance for various populations:

Air Quality Forecast page: which has links to:

Maine DEP's toll-free air quality hotline: 1-800-223-1196

In addition, you may check EPAs AirNow Fire & Smoke map for particle pollution levels:

On Thursday, there may still be smoke in certain regions. Visit the DEP website at for updates.

For additional information, contact: David R. Madore, Deputy Commissioner