Air quality warning issued for Mon Valley
Young children, elderly people, and people with respiratory problems were advised by the Allegheny County Health Department to limit outdoor activities Sunday due to poor air quality.
The health department issued an Air Pollution Warning for the Mon Valley for Sunday and all of Monday.
According to the department, the 24-hour fine particulate matter standard for the Mon Valley was exceeded at an official monitoring station in the Mon Valley, “and is likely to continue.”
The reading, 107 PM2.5 on the air quality index, places the region in the “Unhealthy for Sensitive Groups” category, meaning that people who are sensitive to air pollution may go outside but should avoid prolonged or heavy exertion, especially if they have asthma.
Fine particulate matter, or PM2.5, is a type of pollution made up of a mixture of tiny solids and liquid droplets that are only visible with an electron microscope.
An Air Pollution Warning has been issued for the Mon Valley for the remainder of today and all of tomorrow. The 24-hour PM2.5 standard for the Mon Valley has been exceeded at an official monitoring station in the Mon Valley and is likely to continue. pic.twitter.com/uPvRRNx4Au
— Allegheny County Health Department (@HealthAllegheny) June 18, 2023
The particles can be inhaled by people and can contain hundreds of chemicals, according to the health department website. They are emitted by power plants, motor vehicles, forest fires, and industrial processes.
“Companies most significantly contributing to particulate pollution in the Mon Valley region are required to temporarily reduce particulate emissions,” the department said in a statement.
An area of high pressure over the region is partially to blame for the bad air quality, according to meteorologist John Darnley of the Pittsburgh office of the National Weather Service.
The high-pressure cell is causing a surface inversion and reducing wind, trapping particulates below it, he said.
“When you’re underneath the center of the high pressure, it’s like a dome,” he said. “You have basically no winds and very little flow, until you get on the back side of the high or the front side of the high.”
According to Darnley, the area of high pressure is likely to stick around at least into Tuesday.
Julia Maruca is a TribLive reporter covering health and the Greensburg and Hempfield areas. She joined the Trib in 2022 after working at the Butler Eagle covering southwestern Butler County. She can be reached at jmaruca@triblive.com.
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