Top Cities With Cleanest Air in America

Top Cities With Cleanest Air in America

Pollution is a big issue that affects everyone, and with technology and industrialization on the rise, pollution in the air has been increasing. Research from the World Health Organization shows that 92% of the population lives in areas with unhealthy air quality. This is especially true in cities with high-density populations that are often near industrial sites. However, some cities in the U.S. are doing all they can to keep their air clean and healthy. This is a significant factor in the population's overall health and well-being.

Clean air is " air free from harmful levels of pollutants, such as ozone, particulate matter, and carbon monoxide." These pollutants, including respiratory issues and other serious illnesses, can negatively affect your health. Naturally, the cities in the U.S. that have the cleanest air are located in regions with low levels of industrialization and pollution. In contrast, others have implemented strong air quality regulations and even some programs that can help reduce pollution.

In this blog post, the Airzey team will go over the U.S. cities with the cleanest air, so stick around!

Cleanest Cities in Terms of Air Quality in the United States

It's often difficult for cities to maintain good air quality. Industrial sites and power plants are polluted, giving off a lot of harmful emissions that can significantly decrease overall air quality. For example, advocacy groups in Evansville, Indiana, have been fighting tooth and nail to hold the coal-fired power plants near their city accountable for the number of daily dangerous emissions.

You cannot achieve clean air without human help. We have made our cities dirty, and our responsibility is to clean them up. Now, let's look at some of the cities with the cleanest air in the United States:

Honolulu, Hawaii

Honolulu, Hawaii, is home to some of the most beautiful beaches in the world. Its pristine environment makes it one of the best cities for people who want to enjoy nature without worrying about polluted air. Honolulu is located far away from any principal sources of pollution. 

The island city also has generally stable weather patterns, which do not favor air pollution formation. Additionally, Hawaii is one of the least polluted states. It has strict air pollution regulations, which help ensure that the air quality in Honolulu remains healthy.

Cities With Cleanest Air Honolulu


Portland, Maine

Maine is known for its good air quality. According to data from the Environmental Protection Agency (EPA), the city in Maine with the cleanest air quality is Portland, the largest city in the state. Portland is located on the coast and is known for its clean air, partly due to the city being far from any significant sources of pollution. Maine also has stringent air quality regulations, which help keep the air quality healthy.

Maine has also implemented several effective programs to reduce greenhouse gas emissions in the state. These programs include the Transportation and Clean Energy Programs, both of which aim to improve air quality and clean up the environment by using cleaner public transportation and renewable energy sources.

Cities With Cleanest Air Portland


Bismarck, North Dakota

North Dakota's air quality index is 4.8, which is unsurprising considering the state's rural population. The North Dakota city with the best air quality is Bismarck, located in the state's center. Bismarck's air quality is generally quite good, with low levels of pollutants like particulate matter and ozone. The city is not heavily industrialized and far from major pollution sources. 

The biggest threat to Bismarck, North Dakota's clean air, is nearby wildfires. Ash and soot drift in from Montana, Wyoming, and Utah, which could eventually lower North Dakota's air quality.

 Cities With Cleanest Air Bismarck


Underhill, Vermont

Vermont has exceptionally clean air thanks to its efforts to improve the environment. It has an EPA index score of 38.5 and a U.S. EPA Particulate Matter 2.5 index score of 4.9. The Vermont city with the cleanest air is Underhill. It's surrounded by forests, which can help filter out air pollutants. It is also not located near any primary sources of pollution, which contributes to its clean air.


Cities With Cleanest Air Underhill


Troy, New Hampshire

Troy, New Hampshire, is located in the western part of the state, in the Monadnock region. Troy's air quality is generally good, with very low levels of particulate matter, carbon monoxide, and ozone. New Hampshire's generally clean air has contributed significantly to Troy's good air quality, as has the state's strict air quality regulations. Like Underhill, Vermont, and Troy, New Hampshire, has many forests surrounding it, which helps immensely with the city's pollution levels.

Cities With Cleanest Air New Hampshire

ALT TXT IMG: Cities With Cleanest Air New Hampshire

Air Quality Index Ratio for Clean Air

Image suggestion: Air Quality Index | alt text: AQI chart with the different values

The Air Quality index measures the air quality in a particular location. Governments and environmental organizations typically use it to communicate the level of air pollution in any given area to the public. Let's look at some AQI values below so that you may better understand what certain AQI values mean.

AQI 0-50

An AQI value of 0-50 is in the green zone. Air quality with this value poses little to no threat to human health. Your local air quality is probably pretty healthy if your city is in the green zone.

AQI 52-100

When an AQI value reads 52-100, the area's air quality is in the yellow zone. It's safe to say that the air quality is good in this case, but if you suffer from allergies or asthma, you may experience some respiratory issues.

AQI 101-150

AQI values between 101 and 150 represent that a particular area's air quality is in the orange zone. The air quality here is outside the safe range, as pollution levels are not healthy for those especially sensitive to pollutants and contaminants in the air. This includes people who suffer from any kind of lung disorder or ailment.

AQI 151-200

If the air quality index is between 151 and 200, then it’s considered to be very unhealthy for most people. You will likely experience negative health effects if you venture outside when the AQI is between 151 and 200. Refusing from exercising or working outdoors is a good idea when the AQI is this high.


Worst Air Quality in US


Factors to Determine Air Quality

The Air Pollution Reporting System (APRS) measures pollution levels in the air. It is a network of monitoring stations and other resources used to measure and track levels of air pollution in a particular area. Environmental agencies operate the system, which monitors air quality in cities, towns, and other populated areas. The APRS identifies four primary air contaminants, which we will examine below.

Ground-level ozone pollution

Ground-level ozone pollution occurs when ozone, a toxic gas, is present in the air we breathe at ground level. When sunlight reacts to pollutants in the air, ozone is formed, which can negatively impact human health. Exposure to ground-level ozone can cause respiratory problems, asthma, bronchitis, and other illnesses. It can also cause harm to plants and animals, as well as damage crops and natural areas. 

Ground-level ozone tends to be more severe in the summer when the weather is warm and sunny and in areas with high pollution, such as cities with industrial sites nearby.

Particle pollution/particulate matter

Particulate matter consists of tiny particles that are suspended in the air. These particles inhaled into the lungs can cause adverse health effects, such as cardiovascular and respiratory problems. Particulate matter typically comes from power plants, vehicles, factors, wildfires, and construction sites. The particles may be made up of dust, smoke, and soot.

Carbon monoxide

Carbon monoxide gets produced when fossil fuels are burned. It can cause difficulty breathing, headaches, and dizziness. Prolonged exposure to high carbon monoxide can sometimes cause unconsciousness or even death.

Sulfur dioxide

Sulfur dioxide (SO2) is a toxic gas that gets emitted into the air when fossil fuels, such as coal and oil, are burned (much like carbon monoxide). When released into the atmosphere, SO2 can reach other compounds to form small particles, significantly contributing to air pollution.

Frequently Asked Questions:

What is the EPA?

The Environmental Protection Agency (EPA) protects human health and the environment from pollutants and contaminants in the air.

What are the environmental benefits of a clean state?

The environmental benefits of a clean state include improved air quality, cleaner water, a healthy ecosystem, biodiversity, and more recreational opportunities.

What is Particulate Matter (PM)?

Particulate Matter (PM) is a common air pollutant.

What is the AQI?

The Air Quality Index (AQI) measures air quality in specific areas. The AQI in a particular area is calculated by considering the levels of pollutants in the air.

What are the EPA's Air Quality Monitoring Guidelines?

The EPA's air quality monitoring guidelines include establishing monitoring stations, setting specific standards for air quality, monitoring compliance, and providing information to the public.

Final Thoughts

Many cities in the U.S. boast clean air, thanks to the efforts of the Environmental Protection Agency and local governments, which monitor and regulate air pollution in certain states. The cities listed in this blog post have strict regulations on the emissions of pollutants from industrial sites, power plants, and vehicles. Many also have programs in place to encourage using clean, renewable energy sources. 

Are you interested in learning more about how to keep your air quality safe and healthy? Check out Airzey's selection of air filter products.