WILLIAMSTOWN, Mass. — The state's on an air quality alert through midnight Thursday because of the smoke from wildfires in Canada. 

 

Berkshire residents woke up to smoky, hazy skies and a red glowing sun on Wednesday morning, but with less oppressive heat.  

 

The Department of Environmental Protection issued an air quality alert for elevated levels of fine particles (PM2.5). This refers to microscopic airborne particles measuring 2.5 micrometers or less in diameter — about 30 times smaller than a human hair. These particles come in many sizes and shapes and can be made up of hundreds of different chemicals.

 

The U.S. Environmental Protection Agency says the size of these particles can cause serious health problems because they can get deep into your lungs and even into bloodstreams. Particles less than 2.5 micrometers in diameter pose the greatest risk to health.

 

The air quality statewide is expected to be unhealthy for sensitive groups. These include people with heart or lung disease such as asthma, older adults, children, teenagers, and people who are active outdoors. People with either lung disease or heart disease are at greater risk from exposure to air pollution. 

 

MassDEP advises people in sensitive groups to reduce prolonged or heavy outdoor exertion, take more breaks, do less intense activities, follow asthma action plans, and keep quick relief medicine handy. Watch for symptoms such as coughing or shortness of breath. 

 

EPA's air quality index rates levels from "good" at 0-50 and "very unhealthy" from 201 to 300. Residents of Williamstown can track the AQI through PurpleAir, which displays results from monitors in five sections of town.