In everyday life, some drivers are not even aware of how many harmful substances enter the interior of the car through the ventilation system. This is especially true for older cars. Today, with the COVID-19 pandemic and the loosening of the quarantine regime, the question has arisen: how safe is the car from viruses?
The greater part of modern cars is equipped with cabin air filters. Do they help with the coronavirus situation? To begin with, let’s take a look at what a filter is and what types are found on the market in 2021.
What is a cabin air filter?
The first cabin air filters close to modern salon filters appeared in the early 1990s, but became widespread in the 2000s. Early copies by structure differed little from air filters, which protect engines from dirt. Today’s cabin filters are much more complex in design, although they still look similar. Often it is a rectangle with a rigid shell and corrugated material, similar to cardboard inside.
What kind of filters are there?
Most often cabin air filters are divided into two types: ordinary and charcoal, but on the market there are antibacterial and HEPA. We’ll talk about the latter two a little later.
Simple Сabin Air Filters
The main function of ordinary cabin air filters is to clean the air in the cabin from dust, fluff, some kinds of pollen and soot, that is large and solid particles. With bad smells or filtration of harmful gases they will not help. There are charcoal filters for this purpose.
Carbon Cabin Air Filters
Just like a conventional filter, the charcoal filter is capable of trapping solid particles, but its main advantage is reducing the amount of exhaust and other gases, as well as eliminating unpleasant odors in the car interior. Good ones are capable of reducing nitrogen dioxide concentrations to 0.01 mg per cubic meter, whereas with dusty devices show 0.12 to 0.20 mg/m3.
What about antibacterial and HEPA?
You can find cabin air filters on the market that entice the buyer with promises of antibacterial protection. Doctors and ventilation engineers treat products that use additional impregnation with skepticism. But there is a caveat: all filters are made of a special non-woven synthetic material that does not create a breeding ground for bacteria, unlike paper, for example. That is, they already have antibacterial properties.
But HEPA, or fine air filter, is quite different. It is designed to trap the smallest particles, including PM2.5 and PM10, and is primarily used in medicine.
Such filters can now be found in the Tesla Model S and Model X electric cars, where they are part of the bioweapons defense package touted by Ilon Musk. If you look at the filter that was shown at the presentation, its size immediately catches your eye. And that’s important. HEPAs are capable of passing far less air, so they are made noticeably larger to maintain adequate flow.
You can already find HEPA filters on the 2021 market for many car models. If you decide to get one, you should know that the air conditioning unit will most likely lose efficiency.
The answer to this question is ambiguous. None of the common cabin air filters can contain the virus. Its particle size ranges from 0.1 to 0.12 microns, which is noticeably smaller than the cells of the filter element (up to 0.3 microns).
However, COVID-19 itself does not travel. According to the WHO, it spreads by airborne droplets, and the word “droplet” in that phrase is very important. As a droplet, the particle size increases to 2-7 microns, and virtually any type of filter can do the job of containing the infection.
One more important point. You can catch the disease when the droplets come into contact with the mucous membrane from the respiratory tract of a patient, such as when coughing or sneezing, as well as saliva or nasal secretions. If you sit in a car with the windows closed, you can become infected only if you have a sick passenger nearby or because of your own hands (you touched a dirty surface and got it in your eyes, for example).
It is highly unlikely that the virus will enter the passenger compartment through the air intake, but we should not completely rule out such a possibility. Little is known about the survival of COVID-19 in the air. So far, researchers are of the opinion that it can hang outside the body for up to three hours.
When and how do I change the filter?
The filter is a consumable and must be clean for it to work efficiently. There is no need to go to the service center. There should be no difficulties in changing it yourself, because the filter is a very light part. You don’t even need a special tool.
The location of the filter varies from model to model. Engineers can hide it both under the hood and in the cabin, but the hints are exactly spelled out in the service and maintenance manual.
The life of the elements varies depending on the type, but according to recommendations, you shouldn’t use one filter for more than a year or 9,000 miles. It’s better to change or at least check more often, especially if the car is driven in a big city.
How to choose a cabin air filter
- Find out the catalog number of the original and order it or match the products of other manufacturers only by that number.
- If you buy non-original, make sure the fit is tight. There should not be any gaps.
- It is better to choose a filter that has a laminated coating on the side that faces the fan. Without this, lint can enter the ventilation system.
- The presence of markings of the direction of air flow, as well as designations “top” and “bottom” will greatly simplify the installation. Without problems to put the filter will help and its rigid construction.
- If you choose a charcoal filter, you should give preference to a heavier one. It has more activated carbon, which means it filters better.