Air pollution affects almost every person on earth, and currently shows no signs of abating. A wide range of gaseous and particulate pollutants increasingly contaminates the air we breathe, causing deaths, chronic health problems, and environmental damage.
But the situation is not hopeless; we can do something about air pollution and safeguard clean air for all. In this article, we share 35 ways to reduce air pollution, which covers all its major sources.
35 ways to reduce air pollution
There is no single way to eliminate pollution in the air we breathe, but a combination of technologies and initiatives can drive down emissions of air pollution for sustained improvements in air quality. Here are 35 of the most effective ways to reduce air pollution:
1. Active monitoring of air quality
One of the first steps for tackling the problem of air pollution is monitoring the level of pollution in the air. Authorities can measure air quality using a range of advanced photochemical and optical sensor systems and multi-pollutant monitoring devices. Data collected can then analyze absolute levels and trends in air pollution in a specific area.
Monitoring air pollution has the following benefits:
- Monitoring pollution levels helps authorities and the public understand the scale of the problem.
- Data from air pollution can alert the public about poor air quality that may affect health.
- Air quality monitoring can establish compliance with emissions standards.
- Tracking air pollution levels can help authorities see if air pollution reduction strategies have made a difference.
2. Increase indoor ventilation
Ventilation is one of the simplest solutions for improving the quality of indoor air. In lesser economically developed countries, burning solid fuel and paraffin for heating, lighting, and cooking contributes to indoor air that is laden with harmful particulates and chemicals. Breathing polluted indoor air damages the lungs and long-term health.
Building controls are critical to ensuring that buildings have an adequate level of ventilation. Solutions like windows, vents, and extraction fans mean that damaging particulate pollution cannot saturate room air. Homeowners should retrofit spot and dilution ventilation in properties that lack ventilation to reduce health risks.
3. Use VOC-free building materials and furnishings
Volatile Organic Compounds (VOCs) are harmful substances that are off-gassed from a range of domestic building materials, paints, varnishes, and furnishings. Their prevalence means that they can build up in indoor environments and cause health problems.
Governments have sought to limit the VOC levels of indoor air by setting limits on the levels of VOCs in a wide range of products. The use of low-emitting building materials like insulation makes a significant difference in the impact of VOC emissions with long-term improvements in air quality.
4. Plant trees
Many environmentalists believe trees should be on the frontline of the battle against air pollution. Trees, shrubs, and other vegetation can capture pollutants and improve air quality, particularly in urban and industrial areas.
Trees form a useful barrier against localized pollution sources, removing tiny particles and chemical pollutants from the air via the stomata on their leaf surfaces. Health professionals have found that trees and vegetation in residential areas may contribute to lowering asthma rates in young children.
However, the right kinds of trees must be planted. London planes, poplars, and other tree species emit high levels of volatile organic compounds (VOCs). Beneficial trees include conifers, silver birch, yew, and elder trees.
5. House plants
Plants could contribute to controlling indoor air pollution. The 1989 NASA Clean Air Study investigated the air-purifying properties of a wide range of house plants. Not only did many plant species reduce carbon dioxide and increase room oxygenation, but they also can remove chemicals that include formaldehyde, benzene, and trichloroethylene from room air.
Helpful plant species tested by NASA include:
- Variegated snake plant (Sansevieria trifasciata laurentii)
- Florist’s chrysanthemum (Chrysanthemum morifolium)
- Peace lily (Spathiphyllum ‘Mauna Loa’)
- English ivy (Hedera helix)
- Bamboo palm (Chamaedorea seifrizii)
- Red-edged dracaena (Dracaena marginata)
- Weeping fig (Ficus benjamina)
- Barberton daisy, gerbera daisy (Gerbera jamesonii)
The study found that these plants cannot control indoor air pollution by themselves but supported a beneficial reduction in the level of harmful chemicals when tested in conjunction with a carbon air filter.
6. Prevent wildfires
Wildfires are a key source of air pollution and long-lasting environmental damage in the areas affected by them. Prevention of wildfires is the most effective way to eliminate this source of air pollution.
Authorities and the public can use several strategies to prevent wildfires that include:
- Proactive forestry management. Careful management of trees, brush, and other vegetation can minimize the risk of a wildfire taking hold or spreading. This may even involve the use of targeted prescribed fires to rid forest areas of dead wood and potential kindling.
- Installing areas with basic fire-fighting equipment throughout wildfire zones.
- Prohibiting open fires, campfires, and barbecues in areas that are vulnerable to wildfires. Gas grills may be permitted rather than wood or charcoal.
- Avoid leaving vehicles running on dry grass in hot weather.
7. Air scrubbing technology
Air scrubbers are air purification systems that are used in HVAC systems and industrial settings. These powerful devices are engineered to remove particulates from the air, reducing pollution and making the air breathable. An installed air scrubber uses moisture and condensation (wet air scrubber) or powered filtration (dry air scrubber) to filter the air that enters the scrubber.
How effective are air scrubbers?
Air scrubbers can remove odor and particles as small as 0.3 microns in diameter from the air. Wet air scrubbers and scrubbers that contain special media like activated carbon are effective at reducing the levels of air pollution in exhaust air from industrial processes.
8. Residential air cleaners
Indoor air pollution is one of the largest contributors to morbidity and mortality from air pollution. One of the best ways to reduce air pollution indoors is to use an air cleaner. Residential air cleaners use a range of technologies to reduce or remove pollutants from room air, reducing exposure to respiratory allergens and irritants. Many solutions are filter technologies and can be installed with home furnaces or HVAC systems.
Domestic air cleaners vary significantly in their efficiency of air cleaning and effectiveness. Certified and rated devices can remove particulates and other pollutants from the air measured in a lab. The clean air delivery rate (CADR), measures the rate of delivery of acceptable cleaned air.
9. Electrostatic precipitators
Electrostatic precipitators also offer ways to reduce air pollution. These are filter-free devices that are used in industries that use fossil fuels to remove particle pollution from the air in smokestacks. They are extremely efficient at removing carbon particulates like soot, ashes, and other combustion by-products, removing up to 99% of particulates that are less than 1 micrometer in size.
These precipitators use an electrical current to generate static electricity that ionizes and attracts charged particles to electrodes, removing them from the air. The particles then pass between charged and uncharged components, finally ending up in a hopper where they can be cleaned out.
Baghouses are devices that are used to control air pollution in industrial settings, and are another of the more effective ways to reduce air pollution. They comprise a range of tubes, envelopes, and fabric filter cartridges that capture dust, dirt, and particulates from the exhaust air of a factory or industrial facility.
As waste air moves through the baghouse, removed solid material builds up as a dust cake on the insides of the baghouse.
Once the baghouse is filled with pollution, personnel can clean using reverse air, the shaker method, or a pulse jet. This short video explains the basics of baghouses:
11. Catalytic converters
Catalytic converters are modular components that attach to the exhaust system of a vehicle. Without going into the nitty-gritty, explained very basically – catalytic converters filter out pollutants and harmful byproducts from the exhaust fumes, and burn them up.
These converters can convert over 90% of the carbon monoxide, nitrogen oxides, and hydrocarbons emitted by vehicles. In the petrochemical industry, platinum-based catalysts reduce the energy requirements and pollution generated by the production of gasoline.
12. Particulate filters for diesel vehicles
Burning diesel can be particularly dirty. The soot and particulates in the exhaust from diesel engines are notable contributors to air pollution. In the UK, manufacturers must fit diesel vehicles with diesel particulate filters (DPFs), but unfortunately – they are not a requirement in the USA.
These devices trap and store the particulates in diesel exhaust so they can’t pollute the air. Once installed, it is illegal to remove a DPF.
DPFs eventually become filled and can cause engine problems if obstructed. To prevent this, the filters regenerate by burning off the excess soot. This regeneration can be passive, when the engine is running at high temperatures, or active, with the injection of fuel to drive the burning process.
13. Vehicle particle suction
Many people underestimate tires and vehicle breaking as a source of air pollution. The particles generated by tires rubbing against tarmac may be as much as 1,000 times more polluting than those from exhaust emissions.
This is a particular problem for electric vehicles as their large batteries make them heavier than internal combustion engine vehicles.
Novel devices are being designed and fitted to vehicles like cars, lorries, and trains to address this specific type of fine particle pollution. An example is AMIC ceramic filter technology. It uses an electronic suction and filtration system to retain the fine particles and prevent their dispersal into the air. This universal technology works in all conditions and can be retrofitted to any vehicle.
14. City diesel
Using city diesel is one of the lesser-utilized ways to reduce air pollution, but is very effective. City diesel is a special diesel formulation that has extremely low sulfur levels and reduced particle emissions. City diesel was developed in Sweden, but versions of this fuel are now available in urban areas across the world.
This low-emission diesel reduces particle emissions by up to 84% depending on the vehicle type, engine specs, and particulate type. Low-sulfur diesel also reduces exhaust levels of carbon monoxide, nitrogen oxide, and hydrocarbons by supporting catalytic converter performance.
15. Emissions testing for vehicles
Direct monitoring of the emissions of individual vehicles can also help to curb air pollution. As vehicles age, their mechanical parts wear and engine performance becomes less efficient leading to an increase in the air pollution they emit.
As emissions tests are undertaken when vehicles are stationary, they may not reflect the emissions produced when the vehicles are on the road. However, the tests help to identify the most polluting vehicles and keep drivers mindful of the importance of air pollution.
16. LPG and CNG for vehicles
In congested urban environments, many public transport and transport and logistics providers are turning to Liquefied Petroleum Gas (LPG) and Compressed Natural Gas (CNG) to reduce emissions. These fuels have a favorable emissions profile for carbon monoxide, nitrogen oxide, and non-methane hydrocarbons (NMHC) compared to gasoline and some diesel vehicles.
The methane emissions of LPG and CNG are higher than other fuels but they deliver an immediate reduction in particulate matter and nitrogen oxide to negligible levels. LPG is a preferred fuel for the Clean Air Zones implemented in cities like London and Birmingham, UK.
17. Burning cleaner fuels
Burning fuels that burn more efficiently and thoroughly is one of the most effective ways to reduce air pollution, as these leave fewer soot particles or other pollutants in the air. For example, in 2021, the UK government implemented restrictions on burning bituminous coal and green wood, with approved fuels carrying a ‘Ready to burn’ logo.
By burning kiln-dried wood, approved coal, and manufactured solid fuel like wood pellets in domestic stoves homeowners can reduce their levels of sulfur and smoke emissions. An added benefit is a reduction in the production of the tar-like combustion by-product creosote, which can build up on chimneys and cause fires.
18. Electric vehicles
Electric vehicles (EVs) are being embraced as a solution not only for air pollution but also reductions in greenhouse gasses. The assertion that EVs improve air quality makes sense, especially in urban areas, as they run on electricity and do not produce exhaust.
A transition to a greater proportion of these vehicles on the roads would lead to lower air pollution, in particular:
- PM 2.5
- PM 10
- Polycyclic aromatic hydrocarbons (PAH)
- Nitrogen oxide
Many cities are embracing EV technology as it can significantly reduce air pollution. Delhi, one of the world’s most polluted cities, intends to only sell EVs from 2030 onwards.
19. Hire cars
Car sharing strategies like hiring cars, reduced the number of cars people own and have on the road. By using car-sharing services, individuals can reduce the amount of petroleum that is burned, leading to air that is less polluted by exhaust fumes.
Hire cars also make it less likely that people will use a car for short trips, whereas walking or cycling can be just as quick. These short journeys are the most polluting as the car gets moving from a cold start, and the catalytic converter is not immediately functional.
A reduction in the number of cars would also reduce the heavy pollution generated by car manufacturers. Hire companies can invest in better quality, more efficient vehicles, while users can save on the expense of running a car.
20. Low-emission zones
In many places, municipal authorities have been establishing low emission zones (LEZs) or environment zones, which only allow the cleanest vehicles to travel through them. Authorities monitor vehicles in the zones using Automatic Number Plate Recognition (ANPR). Vehicles that are prohibited receive a fixed penalty notice if they travel through these zones.
London, UK has led the way in implementing LEZs, and now ULEZ. They have been controversial as the fines are high and motorists and businesses have complained about the accessibility of certain parts of the city. Authorities have continued with the zones, advising vehicle owners to replace or modify their vehicles to more compliant models. This video explains how it works:
21. Dust collectors
Dust collectors are used in industrial settings to capture the dust in exhaust air. These are essential for protecting human health and complying with government health and safety legislation. Only dust collectors that meet stringent safety standards may be used.
Dust collectors suck contaminated air from locations where manufacturing processes take place. The air passes through a system of separators and filters which extract the dust and release clean air. Manufacturers must regularly check the concentration of particles in the cleaned air.
22. Treat biofuels with caution
Biofuels receive heavy subsidies and are touted as sustainable and eco-friendly alternatives to petroleum-based fuels. However, biodiesel and other biofuels can generate noxious forms of air pollution. Biofuels can pollute the air at every stage of their production and use. For example:
- The fast-growing poplar and willow trees used as a biofuel source emit significant amounts of isoprene which can combine with other air pollutants to create ozone.
- Studies have shown that this ozone could cause up to 1,400 air pollution-related deaths per year in Europe.
- The surplus ozone generated by biofuel production could also impact agricultural yields, reducing them by up to $1.5 billion.
23. Low-emitting heaters and stoves
Inefficient cooking practices create indoor air pollution that contributes to up to 4 million deaths per year globally. Many poor people have no choice but to use dung, waste, or unseasoned firewood with inefficient heaters and stoves.
Engineers and designers have developed innovative low-cost stove designs that increase the efficiency of fuels and reduce particulate levels. Novel biomass stoves are engineered to burn the fuel more efficiently using insulated combustion chambers and fans. A great example of an improved stove design is the rocket stove which is in use across the world:
Cycling as an alternative to driving reduces air pollution because it takes cars off the road, with an immediate reduction in the amount of air pollution generated. As muscle-powered or electric personal transport, there is no burning or fuel to generate the 1.3 billion cubic yards of air pollution each car generates across its lifespan.
Manufacturing bicycles and e-bikes are also less polluting than cars. Just painting cars adds more than 40 million pounds of pollution to the air each year. And despite not being enclosed in a vehicle, cyclists are less exposed to air pollution than drivers when they travel on the roads.
Short car journeys are the most polluting. They are simply not long enough to warm up the engine so it can burn fuel efficiently and the catalytic converter can operate optimally. Car journeys that are under five miles can emit more than double the pollution produced by a long drive.
Any transport method that reduces shorter journeys will positively impact air pollution levels. The availability and convenience of cars make it easy to jump in one to make even the quickest journey. By opting to walk rather than drive, you can cut these polluting journeys out, leading to lower levels of air pollution in local communities and an improvement in your health.
26. Public transport
Public transport is also a sustainable and less polluting alternative to driving, taking cars off the road and reducing the overall level of air pollution generated by traffic. Transportation is one of the biggest causes of air pollution globally and the main cause of air pollution in cities.
Switching to public transportation in urban areas can produce significant improvements in air quality, especially if buses use LPG or CNG, or biodiesel fuel. Better public transport could also save up to 30 million metric tons of CO2, a 45% reduction in emissions.
In the world’s poorest nations, better public transportation and transport infrastructure could also deliver improvements in air pollution. By improving roads, making them safer, and providing buses and trains that use low-cost, clean fuel, these countries can ease the burden of polluted air in their densely populated urban areas.
27. Reduce aviation sector emissions
The jet engines of aircraft use the most volatile petroleum fuels (kerosene) that burn efficiently, but the aviation sector is still a notable polluter. Not only do airplanes release nitrogen oxide and PM 2.5 particulates in their exhaust, but surface traffic and airport operations also have high air pollution emissions. Nitrogen oxide emissions in flight can also damage the ozone layer.
Emissions standards set by aviation industry bodies like the International Civil Aviation Organization (ICAO) can help to curb rising emissions from this sector. Implementing technologies like selective catalytic reduction and exhaust gas recirculation also reduce the amount of pollution emitted by planes.
Other strategies can contribute to lowering the levels of pollution produced by the aviation sector:
- A reduction in air travel. In 2019, there were over 4 billion passenger journeys by airplane.
- Reducing air freight by moving from a global supply chain to local food production and manufacturing.
- Curbs on the number and size of airports to reduce ground-level emissions.
28. Tackling air pollution from ships
Shipping is a big polluter because of the dirty fuel used by many vessels. ‘Bunker fuel’, the fuel used by the maritime sector, is a thick black sulfur-rich oil that releases large amounts of sulfur dioxide and nitrogen oxide when it is burnt.
The International Maritime Organization (IMO) now requires all shipping fuel to limit sulfur levels to a maximum of 0.5 percent sulfur, from existing limits of 3.5 percent or more. Health authorities have modeled that this capping of sulfur levels could prevent as many as 150,000 premature deaths and over 7 million childhood asthma cases across the world each year.
29. Limit open burning
Many people use open burning for recreation or to burn garden waste. However, indiscriminate open burning releases high levels of gaseous and particulate air pollution, which can be very harmful to health in densely populated areas.
Burning trash is illegal in most places, and many municipalities have taken steps to limit the timing or frequency of open burning in their communities. Many households switch to using a gas-fuelled fire pit for recreational fires or composting garden waste rather than burning it.
30. Reduce landfill use
Dumped waste in landfills releases copious volumes of harmful gasses and obnoxious odors as it decomposes. Reducing dependence on landfills for waste management can help to limit the emissions levels from these sites and prevent landfill from rapidly increasing in number and size.
Recycling and other strategies that divert municipal waste from landfill will reduce the gaseous and particulate emissions from them. Some countries have also sought to clean up existing landfill sites using techniques like capping, air sparging, and the installation of pump and treat systems to reduce their emissions.
31. Implement a layering strategy for landfills
The indiscriminate pouring of waste into landfills leads to uncontrolled decomposition and the development of pockets of methane and other harmful gasses which gradually dissipate into the atmosphere. But even if landfill use cannot be immediately curbed, landfills can be made more sanitary and structured, minimizing emissions and other environmental harms.
Sanitary landfill engineering uses layering to develop landfill sites that prevent the escape of harmful gasses and chemicals. Layered landfills include lining layers of clay and plastic along with controlled drainage and gas collection. Site personnel actively monitor the landfill to ensure that polluting gasses do not escape.
32. Buy locally produced products
People could reduce the air pollution generated by ground, air, and sea by choosing to purchase products and products that have been grown, prepared, and manufactured locally. A reduction in demand for imported goods means that airplanes, trains, trucks, and shipping make fewer polluting journeys.
Opting for local seasonal produce and goods that are made domestically reduces freight mileage, and pressure on supply chains and strengthens the local economy too.
33. Repair, recycle and reuse
Manufacturing is a big polluter, so anything individuals can do to repair, recycle, and reuse items will reduce the need for these polluting industrial processes. This is known as the circular economy. By prolonging the useful life of individual items and recycling or repurposing their components at the end of their usable life, fewer raw materials need to be procured and processed.
34. Reduce household energy consumption
Most countries rely on burning coal, natural gas, or oil to maintain a sustained electricity supply. Power plants that burn fuel, waste, or wood pellets release exhaust gasses into the atmosphere which include sulfur dioxide (SO2), nitrogen oxides (NOX), and carbon dioxide (CO2) emissions.
Over the last 25 years power plants have decreased emissions of these harmful gasses, but, according to the Environmental Protection Agency, levels have risen since 2020. One way to reduce air pollution from power plants is to minimize household energy consumption. Simple ways to cut down on domestic electricity use include:
- Not leaving appliances and devices on standby.
- Turning down thermostats.
- Switching off lights in unoccupied areas of your home.
35. Use renewable energy sources where possible
Fossil fuels provide 80% of the world’s energy, but efforts to include more renewable energy sources could reduce their use and the levels of air pollution that are generated by them. Energy sources like solar, wind, hydro, and geothermal energy, do not require combustion and do not directly emit air pollutants.
As you can see, there are so many ways to reduce air pollution, ranging from industrial components to simple behavioral changes. Polluted, poisoned air does not have to be the future of our planet. However, it will require innovation, investment, and personal effort to ensure that there is clean air for all.