Air Purifiers: Filtering Car Pollution?

Air pollution is a serious issue, and it's no surprise that people want to improve the air quality in their homes and cars. While opening windows is often recommended to improve indoor air quality, outdoor air pollution can be a problem, especially for those living near busy roads or highways. Air purifiers can help cut down on traffic-related pollutants, but do they work for car pollution? Car air purifiers do exist, and they work by filtering the air inside the vehicle, ridding the interior atmosphere of smoke, dust, pollutants, and other respiratory irritants.

HEPA filters

The effectiveness of a HEPA filter also depends on various factors, including the size and strength of the air purifier, the type and amount of pollutants present, and the length of use. For example, gases are incredibly small and require advanced gas filter media, which is why HEPA filters alone may not be sufficient for removing car exhaust fumes. To address this issue, some manufacturers have incorporated HEPA filters into the climate-control system of their vehicles, making them more effective at sterilizing the air than standard cabin filters.

When it comes to portable car air purifiers, placement is crucial. According to the CDC, HEPA air cleaners are likely to be most effective when placed as close to the occupants as possible. In a car, this could mean placing the purifier in a cup holder, on the armrest, or on the dashboard, depending on its size.

It's also important to consider the construction of the air purifier. The case that the HEPA filter is installed into must be airtight. Otherwise, air and pollutants will find the path of least resistance and bypass the filter, reducing its effectiveness. Additionally, frequent replacement of the filters is necessary to maintain their efficiency in removing concentrated pollutants.

Some car manufacturers, like Mercedes-Benz, Tesla, and MG Motor UK, have recognized the importance of in-cabin air quality and now offer advanced air filtration and purification systems as standard or optional features. For instance, MG Motor UK offers a HEPA filter in its 100% electric SUV, the ZS, which is designed to block pollution and odours. Similarly, Honda Motors Europe has introduced a premium air filter to prevent germs, viruses, and allergens from entering the cabin.

Carbon filters

One example of a carbon filter is the EU-funded NOXTEK project, which uses cutting-edge nanomaterials to create an air filter that removes NO2 from polluted air flows. This technology has been shown to reduce in-car concentrations of NO2 by up to 98%. However, it is important to note that NO2 emissions mainly stem from road transport, and other sources of harmful pollutants, such as particulate matter, may still be present in the air.

To address particulate matter, a combination of filtration systems may be necessary. For example, a conventional HEPA filter can address particulate matter from traffic pollution, but it may need to be supplemented with additional technology to address gaseous pollutants. Overall, while carbon filters can be an effective component of air purification systems, they are most effective when used in conjunction with other technologies and considering factors such as the size and strength of the purifier and the specific pollutants present in the environment.

Ionizing air purifiers

Air purifiers can help reduce traffic-related pollutants and improve the air quality inside your home or vehicle. While ionizing air purifiers can remove particulate pollutants from the air, they are ineffective against chemical gases from car exhaust.

The effectiveness of ionizing air purifiers has been called into question. Studies have found that most ionizers are too weak to significantly impact particulate levels. Stronger ionizers can be effective, but they come with the drawback of producing harmful ozone as a byproduct, which is a known lung irritant. The EPA does not recommend using air purifiers that generate ozone due to its potential health risks.

If you're considering an air purifier for your home or vehicle, HEPA filters are a popular choice. They are designed to capture 99.97% of particles at 0.3 microns in size, including PM2.5 pollutants commonly found in vehicle emissions. Additionally, carbon filters are effective at removing airborne chemicals and volatile organic compounds (VOCs).

When choosing an air purifier, it's important to consider your specific needs and the types of pollutants you want to target. While ionizing air purifiers may be marketed as a solution, their effectiveness is questionable, and they may introduce new health concerns with the generation of ozone.

Air purifiers with UV lights

UV light air purifiers work by using UV light to kill viruses and disinfect or sanitize the air. The UV light is designed to destroy viruses and bacteria by disrupting their DNA or RNA, preventing them from replicating and causing infection.

One example of an air purifier with a UV light is the Clorox™ Ultra Air Purifier with UV-C Light. This purifier is designed for extra-large living spaces and provides exceptional filtration beyond HEPA standards. It captures 99.99% of airborne germs and utilizes a 4-stage 360-degree purification system. The UV-C light is used in the final stage to further reduce airborne germs, viruses, and bacteria.

Another option is the Molekule air purifier, which utilizes PECO technology in addition to standard filtration. The PECO technology is designed to remove chemicals commonly found in traffic pollution and mitigate the health effects of airborne VOCs, NOx, and ozone.

While UV light air purifiers may have some benefits in terms of virus reduction, it is important to consider their limitations, especially regarding COVID-19. Additionally, air purifiers alone may not be sufficient to improve air quality, and it is often recommended to open windows and improve ventilation to reduce indoor air pollution.

In-built car air purifiers

Several car manufacturers are now incorporating advanced air filtration systems into their vehicles. For example, MG Motor UK equips select trim levels of its electric SUV with a HEPA filter designed to block pollution and odours. Similarly, except for the Model 3, all Tesla models come with a HEPA filter, and some Volvo models also include a HEPA filter as part of their system. Other manufacturers offering advanced filtration systems include Mercedes-Benz, BMW, Volvo, Hyundai, and Honda.

HEPA filters are highly effective at removing airborne particles, including bacteria, viruses, and exhaust fumes. They are designed to filter out 99.97% of particles at a size of 0.3 microns, which includes tire and brake dust and some elements of vehicle emissions. However, they are not effective at removing VOCs or other gaseous pollutants like nitrous oxides (NOx) and sulfur dioxide (SO2). To combat gaseous compounds, activated carbon filters can be used, which are designed to remove airborne chemicals and volatile organic compounds (VOCs).

While in-built car air purifiers can significantly improve cabin air quality, it is important to note that some pollutants, such as carbon monoxide, cannot be eliminated by any filter. Additionally, it is recommended to follow manufacturer guidelines regarding cabin air filter replacement, which may vary depending on the vehicle and filter quality.

Frequently asked questions