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Tips to Fell Air Quality Foes This Fall

Ahh, autumn in western Pennsylvania - a time to don cozy sweaters, peep colorful fall foliage, and enjoy all things pumpkin spice. But the crisp weather also ushers in serious seasonal foes: inversions and deteriorating indoor air quality.

Our neighbors in the Mon Valley may be familiar with the term inversion, but for the uninitiated: A temperature inversion is an atmospheric condition where warm air lingers above cooler air, trapping air pollutants like fine particulate matter and hydrogen sulfide close to the ground.

Our local topography - all those peaks and valleys - exacerbate air pollution episodes spurred by inversions and fueled by industrial emissions because those pollutants get trapped in lower-lying areas (like the Mon Valley), where inversions keep them from dispersing.


What You Need to Know About Inversions


Locally, we start experiencing inversions more frequently this time of year. Historically, VERY strong inversions have caused spiking concentrations of air pollution and associated malodor.

In fact, these VERY strong inversions occur often enough that GASP and fellow air quality advocates pushed the Allegheny County Health Department (ACHD) to formalize a Mon Valley Air Pollution Episode Rule that requires certain companies to take action to minimize emissions of fine particulate matter during these periods of poor air quality.

The Mon Valley Air Pollution Episode Rule (which you can read all about here) also requires ACHD to issue public Alerts when a Mon Valley Air Pollution Watch or Warning is triggered.

We encourage folks - especially those in the Mon Valley - to be air-aware this fall when it comes to inversions. You can do that by signing up for Mon Valley Air Pollution Episode Alerts here. Please also follow GASP on Twitter/X, Facebook, and Instagram, where we post real-time, actionable information to help you plan your day and mitigate your exposure to air pollutants.

How's the Air In There?


When we say be air-aware, that means indoor air, too. That’s why we thought now - when cooler weather forces us to close up those windows - we wanted to remind you of some of the most common air pollution pitfalls in your home, as well as some steps you can take to make sure you and yours can breathe healthier air there.

Here’s the thing: Recent research has shown that indoor air quality can sometimes be more polluted than one might believe – in some cases more polluted than outdoor air.

According to the EPA, Americans, on average, spend approximately 90 percent of their time indoors, where the concentrations of some pollutants are often two to five times higher than typical outdoor concentrations.

Many pollutants affecting indoor air quality come from sources inside the building themselves. This could include combustion sources like fireplaces, tobacco smoke, and cooking appliances. It could also originate from cleaning supplies, paints, and insecticides or from the degradation of old building materials or new materials that are off-gassing.

We also know indoor air quality can become unhealthy due to outdoor sources of pollution finding their way inside our homes, schools, and office buildings. Outdoor air pollutants can enter buildings through open doors and windows, ventilation systems, and cracks in structures.

Some pollutants come indoors through building foundations. Harmful smoke from chimneys and industrial sources can enter homes to pollute the air in the home and neighborhood. In areas with contaminated groundwater or soils, volatile chemicals can enter buildings through the same process.


Fortunately, indoor air pollution concentrations from individual sources might not pose a serious health risk by themselves. Unfortunately, the majority of homes have more than one source contributing to indoor air pollution.


“There can be a serious risk from the cumulative effects of these sources. Fortunately, there are steps that most people can take both to reduce the risk from existing sources and to prevent new problems from occurring,” the Environmental Protection Agency warns on its website.

We’re talking more than radon and asbestos - we’re talking about other culprits such as dust, smoke, and the like.

Don’t Forget About Those Filters

So, when was the last time you changed your filters? You know, the ones that help keep your furnace and air conditioning systems clean? Do you know the state of your ductwork? Because know this: Having it cleaned can make a big difference, too. If you need some advice on best practices regarding filters and ductwork, the fine folks at the Environmental Protection Agency (EPA) created this handy guide.

What About Adding an Air Purifier?

Perhaps the simplest way to rid your home of air pollutants is running an air purifier in the most-used areas of your living space. Air purifiers range in price and functionality, and there are even ways to create a DIY air purifier – one that requires only a box fan and a standard HEPA (High-Efficiency Particulate Air) filter. Pro Tip: HEPA filters run about $25-$35 and can be purchased at local hardware stores and on Amazon.

Forget the Fireplace

We know there are diehard fireplace aficionados out there, but we have to tell you: Homes with wood-burning fireplaces have elevated levels of indoor air pollution and you may be unwittingly impacting your neighborhood’s air quality too. Consider using your furnace instead of starting a fire and keep the air your family and your neighbors breathe a little cleaner.

If you’re concerned about what’s in the air you’re breathing at home, then please check out Pittsburgh-based ROCIS (Reducing Outdoor Contaminants in Indoor Spaces), one of our partner organizations offering a number of helpful resources.

Editor’s Note: For those interested, ROCIS will soon be starting its latest Low-Cost Air Quality Monitoring Project. We highly recommend you check out the free opportunity. Here’s what you need to know.



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