Car air filters

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In your car

Many people spend a significant amount of time in a car, either as driver or a passenger. When in a car, you can be exposed to allergens or respiratory irritants, which can impact your comfort and driving.

There are ways to minimise this exposure.

What are the potential problems?

Pollen – If there’s pollen around, the air intakes in your car may scoop it up allowing it to be spread into the car interior. This may cause (or exacerbate) asthma or allergy symptoms. If you’re driving, this can add to fatigue, or increase the risk of sneezing (something that is best avoided when driving).

Mould – Air ducts can collect leaves and other debris, which can retain moisture, allowing mould to grow. This might result in a musty smell coming from your car vents. If you are sensitive to mould, you may experience the same problems that we outlined above for pollen.

Pollution – Even with improving vehicle emission standards, cars and trucks produce a significant amount of pollution. You really notice this in a busy tunnel if you have your windows down, or your air vents on fresh-air intake. Some people experience respiratory symptoms when exposed to such emissions.

Reducing the impact

Properly fitted and serviced particulate filters should trap dust, pollens, fungus spores and possibly some pet allergens, while activated charcoal filters are intended to filter toxic, unpleasant and smelly gases, which can also trigger asthma symptoms.

Not all cars have particulate filters fitted as standard, so if you are buying a new car, ask the dealer. Some particulate filters are better than others, with electrostatic filters likely to capture more particles.

Activated charcoal filters are less common. A list of more popular brands and models of car appears on the following page. 


Filters need to be periodically replaced, or they cease to be effective. While a dealer service should schedule this, if you get your car serviced somewhere else, you may need to ask for the filter to be replaced. Some filters can be changed by the owner, although it can be a little time consuming and tricky.

Ducts should be cleaned, particularly if there is a musty smell coming from them.