10 Facts About Air Quality

 

Air quality is a complex topic that influences both our health and the environment. Better understanding air quality, and what affects it, helps us make informed and data-driven decisions regarding our air. Whether it's deciding to go on a run, or installing air purifiers in your office, knowledge of air quality equips you with the tools you need to safeguard your air.

 

1. Airborne lead reduced massively in recent years

Airborne lead decreased by 98% between 1980 and 2014 due to a number of EPA regulatory efforts. The driving catalyst for this decrease was the removal of lead from motor vehicle gasoline. This resulted in "a more than 90% reduction in mean blood lead concentration" in the U.S. (Angrand et al.). Current sources of airborne lead consist primarily of heavy metals processing and leaded aviation fuel used by piston-engine aircraft.

2. Your humidifier could be the problem

There are many sources of indoor air pollution, including cooking, fireplaces, and pets. However, there is one source in particular we want to highlight, as you may not know that it creates pollution. Ultrasonic humidifiers, which normally help to solve a problem in your household, produce a high amount of particulate matter. Due to the way these humidifiers function, the water droplets they disperse into the air can contain particles. When those droplets evaporate, the included particles remain in the air becoming airborne PM.

3. Watch out for winter inversions

Temperature inversions, which occur when a layer of cool air gets trapped under a layer of warmer air, happen all year round. However, they happen more frequently and are stronger in the winter. This is because the winter affords longer nights, which allow more time for surface temperatures to cool. Additionally, snow covers mean the ground reflects light rather than absorbing it, preventing the ground from heating up when the sun is out. This means the air at ground level remains cold while the air above heats up (Utah DEQ).

4. Planes may be cleaner than you think

I know how it can feel on a long plane flight. The seats are cramped, the people are loud or rude, and the air feels stale. However, that stale air isn't necessarily dirty. Most commercial U.S. planes contain High Efficiency Particulate (HEPA) filters that remove 99.7 percent of particulate material from a plane's air according to the FAA. This means that while it might not always feel good, you can breathe easy knowing that your flight's air is clean.

5. We are not meeting W.H.O. standards

In 1987, the World Health Organization (WHO) released a set of air quality guidelines that were meant to push countries in the direction of cleaner air. The guidelines, last revised in 2021, describe acceptable levels of air pollution over different intervals of time including 8-hour, 24-hour, and annual periods. According to the WHO, "in 2019, 99% of the world's population was living in places where the WHO guidelines were not met." Despite this despairing metric, the revised guidelines continue to encourage countries by including interim targets to shoot for as they progress towards acceptable levels.

6. The makeup of wildfire smoke

Wildfire smoke, and smoke in general, is a complex substance. Many chemicals, including multiple criteria pollutants, can be components of smoke. However, out of these pollutants, particulate matter "represents a main component" of smoke, and is a "principle public health threat" (EPA). This is because particulate matter penetrates deep into your lungs and can "cause serious health problems." For information on what to do during a wildfire, refer to the EPA's guide here.

7. We breathe a lot of air

If you've ever been anywhere that's heavily polluted, or have had the misfortune of being near a wildfire, you know how the air can feel: sore throat, headache, difficulty breathing, etc. Those effects are clear. However, when the effects are less tangible, like longer-term issues, it's easy to dismiss air quality as unimportant. But is it important? Well, given that the average human breathes in "just over 2,000 gallons of air" a day, the composition of that air matters (Lung.org). Whether you can feel it or not, what you take into your body does affect you.

8. Understanding acid rain

While acid rain may not be as catastrophically dangerous as it is in the movies, it is still harmful. When acid rain falls, it can damage ecosystems, harm wildlife, and affect other vulnerable parties (EPA). Created when certain air pollutants such as SO₂ and NO₂ react with other substances in the air like water and oxygen, acid rain can occur naturally. However, it is primarily created as a byproduct of human activity (NH Gov).

9. Good vs bad Ozone

You might have heard positive or negative things about ozone. That's not because it's controversial, but rather because ozone can be good or bad depending on its location. But what does that mean? At a surface level, ozone is harmful to human health. But, in nature, ozone doesn't form where it would interact with humans. Rather, it forms in the stratosphere, where it creates what is known as the ozone layer. This layer stops harmful UV radiation from reaching Earth's surface; this is where ozone is good. Conversely, ozone can form at surface level when certain air pollutants react with each other. Because this ozone is now at ground level, and it's toxic to humans, this is where ozone is bad.

10. Monitor the air around you

You can use the PurpleAir Map to monitor the air around you! On it, you can view AQI, particulate matter, and other types of environmental data from sensors near you. Alternatively, you can look at broader trends over a larger area, such as a state or country.

 

Interested in monitoring your air quality? Check out PurpleAir sensors here