Cleanliness: The point of an air purifier is to clean the air inside your vehicle and leave a fresh scent behind. To test cleanliness, we ran the air purifier in our vehicle to determine effectiveness, but we also looked into features each air purifier had to contribute to clean air. If an air purifier came with a HEPA filter, it likely scored higher in our review. The most effective and noticeable changes in air cleanliness after using each air purifier resulted in a higher score for this category. Power source : Most car air purifiers are battery-powered to conserve energy. Some are even rechargeable, using the outlets in your car as a charging source. Others can be installed into the cigarette lighter of your vehicle to run. If you're struggling to find cleaning materials, look online for inspiration on how to create home-made alternatives. Again, be careful with which chemicals you use and make sure you aren't going to risk damaging or discolouring your car.

The Centers for Disease Control and Prevention (CDC) recommends an alcohol concentration of between 60 and 90 percent for disinfection purposes.