What are the 5 major pollutants regulated by the Clean Air Act?

In this blog post, we will discuss “What are the 5 major pollutants regulated by the Clean Air Act?” Firstly, the article will describe the basics of air pollution. After that, the details of the Clean Air Act will be followed by this. Then, the article will cover all details of the criteria pollutants and the pollutants regulated by the Act. In the end, the article will provide detailed solutions to lessen air pollution.

What are the 5 major pollutants regulated by the Clean Air Act?

The Clean Air Act or CAA is one of the most powerful and successful environmental laws in the history of the United States. The major pollutants regulated by the Clean Air Act are as follows:

  • Ground-level ozone
  • Nitrogen Dioxide
  • Carbon Monoxide
  • Sulphur Dioxide
  • Lead
  • Particulate Matter

Let’s first understand the basics of Air Pollution.

What is air pollution?

The introduction of harmful agents into the atmosphere is known as air pollution. The toxic agents are known as pollutants. These pollutants are derived from natural and human activities, and they can be chemical or biological.

Major pollutants present in the air are particulate matter (PM), ground-level ozone (O3), NO2, SO2, and CO. Air also has lead, allergens, bacteria, viruses and volatile organic compounds (VOCs).

Besides climate change, air pollution has become a significant environmental risk to human health. 

What is Outdoor and Indoor pollution?

Air pollution in the outside environment is called outdoor pollution. The examples of outdoor pollution are as follows:

  • Transportation
  • Combustion of fossil fuel
  •  Cooking activities
  • Energy generation and consumption
  • Agriculture
  •  Improper Solid Waste Management
  • Industries and factories
  • Household pollution
  • Celebrations
  • Construction and demolition

Air pollution created inside any closed structure is called indoor pollution. The examples of indoor pollution are as follows:

  • Household activities 
  • Perfumes and fresheners 
  • Cooking fuel/activities
  • Cigarette 
  • Radon 
  • Poor ventilation 
  • Uncleaned furniture 
  • Pets 
  • Asbestos

 There are two leading causes of air pollution- natural pollution (happened due to natural events like dust storms) and anthropogenic pollution (happened due to human activities like combustion of fossil fuels).

Air pollution has shaken the balance of our ecosystem. Since the stone age, humankind has always strived hard to achieve stability and comfort in their life. Finally, we succeeded, which led to the industrial revolution, followed by urbanization and much-needed changes in the lifestyle.

However, in the process of progression, somewhere we left behind the great values of nature, we forgot the support and symbiotic existence of the environment. While human inventions, no doubt, have always helped us to save our lives, it has also given birth to much inevitable stuff. One such thing is air pollution.

Humans have tremendously exploited natural resources such as fossil fuels in the constant chase of becoming the best in every term and during the development of energy and manufacturing sectors. But, unfortunately, such combustion of fossil fuels for various purposes such as transport and energy releases lots of toxic gaseous and solid contaminants such as carbon monoxide, noxious gases and particulate matter. 

The ever-growing menace of air pollution has also created other challenges such as global warming, greenhouse effect and climate change. These challenges have affected the whole world greatly.

Now, let’s know about the Clean Air Act.

What is the Clean Air Act all about?

In the first half of the 20th century, industries and factories were deteriorating the nation’s air quality. This was because of the fewer regulations in the laws. Escalating emission levels led to a rise in respiratory ailments such as emphysema and asthma. In addition, the smog conditions cost hundreds of deaths and tremendous economic losses. In case you don’t know, smog is a condition where toxic pollutants such as ground-level ozone and particulate matter are trapped at the surface of the Earth and cause visibility issues.

The rising sulphur emissions from the power plants also led to acid rain. These acid rains affected the productivity of the crops too. Understanding the increasing air pollution as a crisis, the Clean Air Act was passed in 1970. It was further made stringent in 1977. Additionally, further amendments were made in 1990.  

This year would mark as 51st anniversary of the Clean Air Act. This Act’s implementation has turned into a boon for the United States. It has turned into one of the most successful laws implemented in American History. This Act, along with EPA, significantly reduced air pollution in the Country.

Statistics say that around 70% of the emissions have been reduced over the past 50 years. The improving air quality has steadily increased the life expectancy of millions of Americans. Moreover, the Clean Air Act has successfully saved the greenbacks from disappearing in the sky. Economists observed that the financial conditions of America significantly improved after the implementation of the CAA.

Between 1990 and 2018, the levels of harmful chemicals have dropped drastically. There have been limits set on dangerous, dangerous, and common air pollutants like sulphur dioxide and nitrogen oxides. The United Nations Environmental Programme has also noticed that levels of carbon monoxide dropped by 74%, whereas ground-level ozone declined by 21%. Additionally, lead has decreased by 82% from 2010. The drop in the lead levels prevented children’s loss of between two and four IQ points.

By 2020, the US EPA has estimated that the Act prevented over 230,000 premature deaths. Moreover, respiratory diseases such as chronic bronchitis and asthma also decreased. Besides, many environmental resources have benefits due to reduced levels of air pollutants. For example, the soil quality in the States have improved; the water bodies and vegetation have also enhanced.

In terms of the economic front, the Act’s enforcement has only boosted the nation’s economy more. The implementation of the Act cost about US$65 billion. But its measures and laws have saved much more money for the citizens. For example, the improved air quality increased work productivity and reduced medical bills. The Environmental Protection Agency has estimated that around US$2trillion in benefits.  

Paul Billings, a senior vice president at the American Lung Association, proclaimed that the Clean Air Act had been the most powerful environmental law of the twentieth century. He further pointed out that the lawmakers drafted the Act considering the future evolution of scientific and technological advances, proving a hit formula.

As you all know, the Clean Air Act regulates the criteria air pollutants, but why are they called criteria air pollutants, and what are those? Let’s find out about them.

Why some of the pollutants are called “Criteria Air Pollutants”?

As you know, air pollution widely disrupts human health and impacts adversely the other facets of the environment. EPA has recognized national ambient air quality standards (NAAQS) for six of the most well-known airborne pollutants such as carbon monoxide, lead, ground-level ozone, particulate matter, nitrogen dioxide and sulphur dioxide. But then, you must be wondering why only six of the air pollutants are selected and called “criteria”. These contaminants are widely present in the ambient air due to many artificial and natural sources, and thus they are called criteria air pollutants.

While the primary NAAQS are set to protect public health, EPA has also set up secondary NAAQS to protect the citizens from the hazardous effects of criteria pollutants. This also includes protection against visibility impairment and damage to animals, crops, foliage and structures. In addition, as per the Clean Air Act, EPA conducts widespread and detailed reviews regularly. This review consists of the scientific literature of health and welfare effects linked with the exposure to these criteria air pollutants.

Who is most vulnerable to these criteria air pollutants?

Children are most susceptible to air pollution as their lungs and organ systems are still developmental. Besides, some of the children may have pre-existing diseases such as asthma. Therefore, estimating the impacts of criteria air pollutants in children has been the main focus of recent NAAQS reviews. In addition, there are also updates of lead, ozone and particulate matter standards to strengthen public health protection. Also, some of the air quality standards are designated to protect the public from short-term and long-term exposure to pollution.

Let’s see these pollutants in detail.

The Five Major Pollutants regulated by the Criteria Air Pollutants

Ground-level ozone

Ground-level ozone is a secondary air pollutant formed due to the reaction of various pollutants emitted by vehicles, industrial facilities and electrical utilities. The ozone precursors can also be developed due to natural sources such as trees. Ozone is formed when heat and sunlight cause chemical reactions between nitrogen oxide and volatile organic compounds.

While atmospheric ozone benefits humans and protects the earth from harm, the artificial ozone layer formed in the stratosphere can threaten living organisms. Short-term exposure to ozone can cause many respiratory ailments, such as inflammation of the lung lining. It can also reduce lung functionality. Brief exposure to ozone can cause shortness of breath, coughing, wheezing, chest pain and burning sensation in the chest. Therefore, EPA has recommended not to exercise outside when ozone levels are high. In addition, exposure to ambient ozone causes asthma, bronchitis and premature mortality. Long-term exposure to ozone can permanently damage lung tissue. It can also develop asthma in children who frequently exercise outside.

Particulate matter

Particulate matter or PM is the mixture of solid particles and liquid droplets detected in the air. You can see particles like dust, dirt or smoke with your naked eyes. However, some are so tiny that they can be seen only under an electron microscope.

The types of particulate matter are PM10 and PM2.5. PM10 are coarse particulate matters which your nose can inhale. The diameters of such particles are 10 micrometres and smaller than that. PM2.5 are fine particulates having diameters of 2.5 micrometres and smaller. Do you know how these particles are smaller? For example, the diameter of your single hair strand is 70 micrometres, which means that it is 30 times larger than the largest fine particles. There are also ultrafine particles whose diameters are less than 0.1 microns.

These pollutants can be organic and inorganic. Examples of particulate matter are metallic particles, pollens, soot, etc. Its size and composition details depend upon its origin.

Particulate matters are formed from various sources. For instance, the agricultural sector produces great amounts of particulate pollution. The farmlands usually contain unpaved roads, which can generate such pollution. Then, the other sources are flour, tea dust, the exhaust of machinery used for agriculture and pollens of the fruit plants. The winds can carry all these particulates to other distant places and lead to particulate pollution. This was an example of anthropogenic or human-caused pollution. Now let’s see another one. The wildfires generated can produce tremendous amounts of particulate matter in the air and transport them to nearby regions. Thus, every activity happening on the earth will ultimately contribute some particulates into the air. In the United States, such as national parks and wilderness areas, the fine particles can cause haze conditions and reduce visibility.

These particulate matters are so microscopic that if they are inhaled, they can cause serious health issues. Fine and ultrafine particulates can deeply penetrate the lungs and anchor them to the lung tissues. This causes chest pain and congestion. Such invasion of particles causes inflammation of the respiratory system, leading to irritations. Such kind of impairment of lung functions can result in many diseases. Besides, these pollutants can also absorb in the bloodstream, and thus the blood circulating in the body can be oxygen-deprived. It ultimately weakens the immune system. 

Sulphur Dioxide

Sulphur dioxide is primarily found in the lower atmosphere. It is a colourless gas and has a pungent, unpleasant smell. When dissolved in water, sulphur dioxide forms sulphurous acid (H2SO3).

Approximately 30% of sulphur dioxide present in the air is transformed into sulphate aerosols or acid aerosols. These traces can be detected in the wet and dry deposition of acids. In addition, another oxide of sulphur, sulphur trioxide (SO3), is also emitted directly into the atmosphere. They are also derived from sulphur dioxide and is rapidly converted into sulphuric acid (H2SO4).

In the United States, fossil fuel is also combusted for electrical utilities and industries. Thus, it’s the primary source of sulphur dioxide. Fossil fuels containing sulphur content can produce plumes of sulphur oxide emissions. Additionally, sulphur dioxide is also generated by roasting metal sulphide ores. Moreover, around 35 to 65% of total sulphur dioxide emissions are produced from natural events such as volcanic eruptions. Volcanic eruptions can often lead to acid rains that threaten the environment. Thermal power plants may also use coals containing high sulphur content or oils which releases sulphur dioxide into the air. The other examples are industrial boilers, the transportation sector and non-ferrous metal smelters.

Contact with sulphur dioxide can decrease lung function efficiency and increase the risk of multiple respiratory diseases. The other symptoms of this gas are irritation of the eyes, nose and throat. It can also lead to premature mortality. Children and elderly citizens suffering from existing respiratory ailments are at particular risk. The sulphate aerosols released into the air can also combine with the particulate matter and irritate chest and chest pain. In addition, sulphur dioxide can dissolve in the watery fluid present in the upper respiratory system and get further into the bloodstream. Besides, research in the United States has shown that plants exposed to high levels of sulphur dioxide can lose their leaves and become less productive. As a result, the trees can die prematurely.

Nitrogen Dioxide

Nitrogen Oxides (NOx) are toxic and highly reactive gases formed when fuel is combusted at high temperatures. The nitrogen oxides consist of significant compounds such as nitric oxide (NO) and nitrogen dioxide (NO2). Other toxic family members are nitrogen monoxide (N2O) and nitrogen pentoxide (NO5). Nitric oxide (NO) and nitrogen dioxide (NO2) are produced by cars, trucks, buses, power plants, and non-road engines and equipment. This generated NO is rapidly oxidized into NO2 in the atmosphere.

As described earlier, these gases are formed due to the burning process of fossil fuels. This product is obtained after directly combining atmospheric oxygen and nitrogen in flames. You can get nitrogen oxides naturally by lightning and small traces from microbial processes in soils. The NOx gases can be brownish.

The automobile sector produces all nitrogen oxides. Commutes include trucks and non-road vehicles such as construction activities, boats and ships, planes, etc. Also, many industrial processes such as power plants, substantial industrial boilers, cement kilns and turbines contribute to nitrogen oxides in the air.

High levels of nitrogen dioxide can cause a hazard to the human respiratory tract. It can increase the susceptibility to various respiratory infections and asthma. Prolonged exposure to elevated amounts of nitrogen dioxide can result in chronic lung disease. It can also affect the smelling ability of humans. Also, nitrogen oxides can affect environmental resources as they can harm the green covers of the Earth. Additionally, it can damage the foliage and hamper the developmental growth of the plants. As a result, this can affect crop yields, resulting in food insecurity.

Carbon Monoxide

Carbon Monoxide or CO is colourless and odourless gas released during the combustion process. The elevated levels of this gas, when inhaled, can be dangerous. Carbon monoxide can be found in the outdoors and indoors too. However, one of the most significant gas sources is the transportation sector.

Vehicles such as cars, trucks, etc., use fossil fuels such as petrol, gasoline and diesel. Their combustion generates this gas. In addition, the machines used in the industries and energy generation sector also produce plumes of carbon monoxide emissions in the air. But that’s not all. Back at home, a variety of kitchen appliances release this gas. These appliances are gas space heaters, leaking chimneys, furnaces and cookstoves.

This can significantly affect the indoor air quality causing discomfort in breathing. It can also generate ad exacerbate asthmatic symptoms. The other significant dangerous effect is that high levels of carbon monoxide inhalation can reduce the amount of oxygen that can be transferred in the bloodstream to the crucial organs such as the brain and heart. Thus, such upsurge levels of CO indoors can cause dizziness, confusion, unconsciousness and even death. Besides, the short-term exposure to high amounts of carbon monoxide may cause reduced oxygen to the heart. This condition can lead to chest pain, also called angina.

Carbon monoxide is also called an indirect greenhouse gas. Again, it’s because it has vital indirect impacts on global warming. When released in the air, carbon monoxide reacts with hydroxyl (OH) radicals in the atmosphere. Thus, carbon monoxide indirectly increases the global warming potential of these gases. In addition, this gas in the atmosphere can also lead to secondary pollutants in the tropospheric layer known as ozone.

What is the other pollutant regulated by the Clean Air Act?


In the past, gasoline combustion in motor vehicles such as cars and trucks released lead emissions; thus, the transportation sector was the primary source of lead emission. In the mid-1990s, leaded gasoline for vehicles was scrapped in the United States. However, the industrial sources, including lead smelting and battery recycling operations and piston-engine small aircraft, still contribute to the remaining sources of lead air emissions.

Lead is hazardous to human health as it accumulates in bones, blood and soft tissues. Moreover, exposure to lead can impact the central nervous system development in young children. This further results in neurodevelopmental effects such as lowered IQ and behavioural problems.

What are the Air Quality Standards set up by NAAQS?

Environment Protection Agency (EPA) has determined the air quality index (AQI) to know the air quality you inhale. The table given below will show how the air quality index looks like.

Air Quality Index (AQI)Levels of Health Concern
(When the AQI is in this range)(air quality conditions are)
0 to 50Good           
51 to 100Moderate
101 to 150Unhealthy for Sensitive group
151 to 200Unhealthy
201 to 300Very Unhealthy
301 to 500Hazardous

The primary purpose of AQI is to inform residents about the impact of local air quality on their health. The Environment Protection Agency calculates the AQI for five major pollutants: ground-level ozone, particulate matter, carbon monoxide, sulphur dioxide, and nitrogen dioxide.

The meaning of the Air quality index as mentioned earlier categories are as follows:

Air quality is considered satisfactory; air pollution is of little or no risk.
Air quality is acceptable; some pollutants present in the air might be dangerous for a minority of people who are very sensitive to air pollution.
Members of sensitive groups may get ill effects. However, the general public is likely not to get affected.
This air quality level can pose a threat to everyone. However, members of sensitive people may experience more severe effects.
Emergency level of air quality; Entire population might be affected
Health alert: Every person breathing such air quality may get serious health issues.

 Thus, it is clear that excluding the first two levels are relatively good to venture out and to do various outdoor activities. However, the last three levels will give you or other adverse effects by inhaling dirty air. 

Below, I will elaborate on detailed solutions to mitigate air pollution.

  What can I do to protect myself from air pollution?

I will elaborate on some of the measures to protect yourself from air pollution.

Personal Hygiene

You can also fight the effects of air pollution by maintaining personal hygiene:

  • You can cut your nails short to avoid the accumulation of dirt. 
  • You can also practice mouth gargling after coming home to free your mouth from unwanted guests.
  • You can also brush twice a day to keep airborne infections at bay.
  • You can also take steam therapy at home to cleanse your lungs.

Quit Smoking

Smoking cigarettes, hookahs (shisha), electric vape or any other types of cigars are not at all suitable for your health. It’s best to stop smoking. Active and passive smoking provides the direct entry of harmful pollutants into your body. This causes the risk to your respiration and other organs dependent on it. 

Physical Exercise 

Physical activities have many benefits to your body. It not only improves your stamina and immunity levels but also helps to increase your lung capacity. Yoga, sanas, swimming, running, cycling, brisk walking and dancing are some of the best forms of exercise to improve your health.

Breathing Exercise 

The majority of people in the world don’t breathe properly. However, correct breathing techniques can keep illnesses due to air pollution at bay. A pranayama is a form of yoga asana which helps to improve breathing methods and lung functionality.

Some of the pranayama types that help you fight air pollution are Kapalbhati, Anulom Vilom, Chandra Nadi, Surya Nadi and Bhastrika. It is strongly recommended to learn this art of breath from a well-certified yoga trainer. 

You can also increase your lung muscles by simply taking a deep breath and holding it for a count of 10. Then, slowly breathe out the air. If you can keep your breath for a longer time, then you have good lungs health.

Good diet 

Always go for a well-balanced diet to remain fit and strong. Consistent eating of junk and fast food will increase the risk of obesity and other diseases. In addition, such people are more vulnerable to the adverse effects of air pollution. Instead, add more fresh veggies and fruits to your diet. Also, you can consume less meat to minimise carbon footprints.

You can also add anti-inflammatory foods as these types of food help to cleanse your lungs effectively. Anti-inflammatory foods which I recommend are: 

Immunity booster drinks

You can do your immunity booster drinks by using readily available items in your kitchen. Immunity booster drinks help to cleanse your lungs. Some of the DIY immunity booster drinks are as follows:

  • Take a glass of warm white milk. Add half a teaspoon of turmeric powder to it. Also, add two strands of saffron to it. Drink it at night before sleeping. You will get good sleep, and you will be relieved from chest congestion. 
  • Boil water by adding half cinnamon stick. Drink the spice-infused water once a day. Your sinuses would be cleared up. 
  • Buy an excellent green tea. Prepare a green tea by following the packet instructions. Have it whenever you feel irritation in your throat. 
  • Take some crushed 1 or 2 peppercorns, a half-inch of a blade of lemongrass and 1 inch of grated ginger and half a teaspoon of turmeric powder. Add everything in one glass of boiling water and reduce it to half a glass. Drink two tablespoons of this spice-infused warm water every after three hours. Adding honey is optional. 
  • You can also drink warm water and add honey if you want. Honey helps to relieve throat irritation.

Use Mask

Mask can prevent you from inhaling the polluted air. You would be able to work in contaminated areas without any fear of allergy infections and stress. 

Masks I recommend

Name Why I recommend it
BASE CAMP CROSSDUST MASKEAPI Filter Technology & Advanced NanotechnologyUser FriendlyMore Durable Six layers face maskFilter materials of the dust mask: Double-Layer Melt-blown with Electrostatic Adsorption Performance, Activated carbon, Non-woven Polypropylene
NIOSH approved N95 maskFour layers mask Flexible nose pad, dual strapsDisposable maskEasy to breathe
BASE CAMP Reusable Cloth Face MaskThree layers mask; 100% cotton Skin-friendly and breathablePocket to add additional filterReusable Mask

How can I individually reduce air pollution?

You can always try your level best to minimise air pollution. The following are the methods to reduce air pollution at an individual level.

Plant Trees

Encourage tree plantation drives amongst the communities. You can be a green saviour of your region. Trees are the natural air purifiers of the environment, and it supplies us with clean air.

Municipal councils or the local authorities can develop urban forests to increase the green cover of the locality. They can also plan to create vertical green walls to improve oxygen levels of the region naturally. But don’t forget to plant only indigenous trees. 

Human/ religious celebrations in eco-friendly ways 

Nowadays, many couples celebrate gender (of their baby) revealing parties by bursting firecrackers. But, unfortunately, these firecrackers can transform into massive wildfires if they are burst near trees.

Thus, you can celebrate such celebrations by planting trees in your nearby barren land. Bursting firecrackers on any religious, festive or personal occasion are only going to harm your loved ones. 

You can also celebrate Christmas by not cutting Christmas Trees. Instead, you can buy artificial ones and use them in the coming years too.

Discourage Plastic

Single-use plastic has been one of the major concerns in the environment. Plastic pollution indirectly contributes to the degradation of air quality. Plastic, when burned, releases various toxic gases such as dioxins into the air.

Encourage alternative use of the plastic product. For example, you can wear a cloth bag for shopping. You can also carry your travel cutlery set to a restaurant. Additionally, you can take your water bottle instead of purchasing a packaged drinking water bottle every time.

Use of public transportation 

Increase the use of public transport to reduce air pollution and traffic congestion. You can also try carpooling or the cab sharing option. Then, you can also use bicycles instead of scooters. Lastly, you can always opt for walking a shorter distance. 

Alternative use of fossil fuel

It would be best to try switching to other fuel alternatives. For example, don’t use wood for the fireplace. Instead, you can wear multiple layers of clothes for warmth. In this way, you can conserve energy. Additionally, you can also install solar panels on house roofs to convert solar energy into electricity. 

You can also buy electric and hybrid vehicles to minimise tailpipe emissions. Finally, propose or discuss a plan with your mayor or any relevant local authority to promote your region’s renewable energy sector.

Reduction of personal carbon footprints

You can also keep a check on your carbon footprints. For example, you can delete unwanted photos, videos or emails from clouds and email boxes as and when possible. Unfortunately, this unwanted stuff takes a lot of energy, which indirectly contributes to air pollution.

You can also switch off the lights and electrical appliances of the vacant rooms. Try buying local products instead of imported ones. Be vocal about them. You can also discover your own country rather than travelling to different ones.

Create Awareness

Air pollution is unpredictable; air pollution in your vicinity can affect people living in Asia and vice-a-versa. However, you can create public awareness about air pollution amongst your community by teaching and interacting with your kids about the importance of good air. 

Educate youth by telling them the ill effects of poor air quality. Then, let your country’s future know that they deserve a better place to live!

How can the local authorities improve the air quality of your region?

You can always observe the changes happening in your surrounding nature. If you experience bad air quality or any activities producing air pollution, you can always concern relevant local authorities or the mayor.

Here are some methods which local authorities can do.

Proper disposal of waste 

Improper solid waste management of an area is an invitation to many diseases and infections. In addition, burning solid waste in public can cause air pollution, although such practices are rare in the US. 

The wastes are mainly disposed of in the engineered landfills and recycled before final disposal to landfills and waste incinerators. 

In addition, waste incinerators help to convert waste into energy.

However, many researchers have claimed that gasification technology or waste-to-energy technology may release harmful gaseous contaminants. Thus, it is necessary that waste collectors rigorously segregate the waste before sending it to waste incinerators. 

The best solution is to minimise waste at a personal level. Statistically, 70% of the waste generated can be recycled effectively. Thus, strive to recycle your waste at a personal level as much as possible.

Reducing air pollution from agriculture

Stubble burning is still practised in some parts of the US. This event contributes to the degradation of air. Local authorities can help farmers convert this waste into cattle fodder or be transformed into pellets as fuel. In addition, farmers should stop the usage of harmful pesticides or fertilisers to decrease air pollution.

How can I reduce indoor air pollution?

Maintaining household or indoor hygiene

You can decrease poor air quality by adequately maintaining indoor hygiene. For example, you can frequently clean your cupboards and open decks to avoid an accumulation of dust particles. You can then vacuum your carpets and sofas at least twice a week. 

Make sure your doggies and cats are well-groomed. Use chimneys and exhaust fans in kitchens. You can also install an exhaust fan in washrooms. Always make sure you are keeping your house well ventilated. 

Keep doors and windows open when possible. Maintain the health of electric appliances such as heaters, humidifiers, AC, fans, air ducts and so on at regular intervals of the year. Avoid overuse of strong perfumes or strong scented candles indoors. You can additionally use indoor plants to make your indoors more lively and fresh.

Indoor plants

Indoor plants do the same work as outdoor ones- they help to purify indoor air naturally. These indoor plants are also easy to maintain.

The indoor plants which I recommend are as follows: 

Air purifiers

Air purifiers help to improve indoor air quality. The risk of getting air pollution-related diseases decreases due to the use of air purifiers. Air purifiers having good HEPA filters do an adequate job of filtering pollutants.

Air Purifiers I recommend are as follows:

NameWhy I recommend it
Blueair Pro XL Air Purifier99.7% of airborne pollutants such as mould, allergens, smoke particles and pollens are captured. 
AIRMEGA 400SReduction of 99.97% of particulates of 0.3 microns. Also responsible for reducing more than 99% of VOCs, NH3 and CH3CHO.Washable and permanent pre-filters are available 
Blueair Pure 121Includes 3-part filtration system. Captures 99% of common airborne PM 2.5 pollutants such as allergens, odours, smoke, mould spores, dust mites and pet dander.An activated carbon filter removes common odours caused by smoke, pets, and gases (VOCs) and smoke caused by wildfires.


The humidity levels in the office should be maintained between 30 and 50% in the office. This range helps to keep dust mites, mould and other allergens under control. In addition, when AC or heater makes the air in the room dry, humidifiers can maintain correct humidity levels.

Humidifiers I recommend

Name Why I recommend it
Amazon Basics Ultrasonic Cool Mist Humidifier 4 litre of tank capacityAuto shut-off feature and 12 or 24-hour timer settingsIt can be used in both seasons
MOVTIP HumidifierPortable Mini-humidifier500 ml capacity, still produces longer mistsEasy to operate
LEVOIT HumidifierIt can be used for both seasons6 litres of capacity Easy to clean and has a remote control


Dehumidifiers also work similarly to humidifiers. It controls the high levels of humidity in the office.

Dehumidifiers I recommend

Name Why I recommend it
Pro Breeze DehumidifierCan extract 50 pints of moisture a dayEnergy-saving auto-off systemBuilt-in Humidity sensor
HOmeLabs DehumidifierEliminates moistness, odour controllerEasy to cleanRemovable water tank
TCL Portable Dehumidifier20 pints of moisture removed per dayIt can be operated at low temperatures tooEasy to maintain

Other FAQs about Air Quality that you may be interested in.

What are the 5 types of pollution?

What are the 6 types of air pollution?

What are the 7 criteria for air pollutants?


In this blog post, we discussed “What are the 5 major pollutants regulated by the Clean Air Act?” Firstly, the article described the basics of air pollution. After that, the details of the Clean Air Act were followed by this. Then, the article covered all details of the criteria pollutants and the pollutants regulated by the Act. In the end, the article provided detailed solutions to lessen air pollution.

Frequently Asked Questions (FAQs): What are the 5 major pollutants regulated by the Clean Air Act?

Was the Clean Air Act effective?

The Clean Air Act was significantly successful. After implementing the Clean Air Act, more than 200,000 premature deaths and 18 million cases of respiratory illness in children were prevented; this was achieved in its first 20 years.

What was the major success of the Clean Air Act?

The following were the major success of the Clean Air Act:

  • Removal of lead from gasoline
  • Decrease in the chlorofluorocarbons and other substances which are responsible for the atmospheric ozone layer depletion
  • Reduction of sulphur emission levels from power plants and transportation fuels.

What impact did the Clean Air Act have?

Since its implementation, the Clean Air Act has continued to lower pollution levels and protect American families and workers. In addition, the United States has also observed fewer premature deaths and illnesses related to air pollution. As a result, the Americans experience longer lives, better standard of living, significant productivity levels and lower medical expenses.

Has air quality improved in the US?

Since 1970, the application of the Clean Air Act, technological advancement and public awareness of the US citizens has drastically improved the air quality in the US. Since 1970, around 77% of the precursor pollutants have dropped.

Who benefits from the Clean Air Act?

American families and workers have benefitted from the Clean Air Act. So far, 370 000 premature deaths have been avoided. The other benefits are fewer hospital admissions for cardiac and respiratory illnesses and net economic benefits of up to USD 3.8 trillion for the US economy.

What is the Clean Air Act 2021?

The new Clean Air Act’s regulations order that newly built pollution emitters follow the new source performance standards that protect public welfare. Besides, the act also includes a list of harmful air pollutants and establishes air quality control regions called attainment areas.


40th Anniversary of the Clean Air Act. EPA. Available at: https://www.epa.gov/clean-air-act-overview/40th-anniversary-clean-air-act  

A success story, with many chapters still to come. Earthjustice. Available at: https://earthjustice.org/features/campaigns/a-success-story-with-many-chapters-still-to-come  

Criteria Air Pollutants, US EPA. Available at: https://www.epa.gov/sites/production/files/2015-10/documents/ace3_criteria_air_pollutants.pdf

Evolution of the Clean Air Act. EPA. Available at: https://www.epa.gov/clean-air-act-overview/evolution-clean-air-act

Gardiner, B., 2020. The Clean Air Act has saved millions of lives and trillions of dollars. Environment. Available at: https://www.nationalgeographic.com/environment/article/clean-air-act-saved-millions-of-lives-trillions-of-dollars?loggedin=true

Palmer, B., 2016. Our greatest environmental success is at risk. NRDC. Available at: https://www.nrdc.org/stories/our-greatest-environmental-success-risk  

Summary of the Clean Air Act. EPA. Available at: https://www.epa.gov/laws-regulations/summary-clean-air-act  

The Clean Air Act. Available at: https://www.biologicaldiversity.org/programs/climate_law_institute/global_warming_litigation/clean_air_act/index.html  

The United States clean air act turns 50: Is the air any better half a century later? UNEP. Available at: https://www.unep.org/news-and-stories/story/united-states-clean-air-act-turns-50-air-any-better-half-century-later