We have worked with most of the brand name cabin filters. The quality of the filters vary greatly, but since there is no quality rating it’s impossible to know how good each filter really is. Another problem with cabin air filters is they don’t all fit tightly, which allows unfiltered air to pass through. These two facts inspired Breathe Purified o2 to begin researching air filter technology, and try to figure out how to fix these short comings.

One of the challenges to finding a better filter solution is that filter sizes range greatly between different makes, models, and years of vehicles. The only approach that made sense was to start with filter sheets that can be cut to size. The great thing is you can get a filter sheet with any MERV value. Since this sheet can be cut to size we cut is a little larger than the filter compartment so it fits tight with no air leakage. We have MERV 8, MERV 10, And MERV 13 filter offerings.

So why would you ever use less than a MERV 13 filter? The higher the MERV rating the better the filter but unfortunately the more air restrictive the filter is. Through extensive testing we have found that few vehicles have the blower capacity to push adequate air through MERV 13 filters. In fact, most vehicle blowers perform best with MERV 8 filters. Our approach is we first attempt a MERV 10 filter. If the air flow is good we settle with the MERV 10. About 35% of vehicles can handle MERV 10 filters. If the air flow is strong, we upgrade to a MERV 13. About 10% of vehicles are able to handle a MERV 13. If the air flow is too restricted, we downgrade to a MERV 8. About 55% of vehicles end up with a 8 MERV. If you look at the above chart, MERV 8 is still a very good filter. Interesting Note: Some cabin air filter brands advertise that their filters are HEPA grade. Real HEPA filters are MERV 17. Based on our extensive testing, It’s hard to believe that a true HEPA MERV 17 filter would allow any air flow past the filter.