If you can afford a Tesla, and have a few extra bucks laying around to order it with Bioweapon Defense Mode… this article is not for you. However, if you’re like us and want a similar level of protection in your current daily driver; you’re in the right spot. We’re about to discuss replacing your current air cabin filter with a HEPA unit. And, that’s about as close as you can get to car air purifier Nirvana without handing over a bunch of cash to Elon.
We’ll also cover a couple other options. Like stand alone units similar to Philips’ GoPure models. And, the ones we think you should really avoid. Like those ridiculous little “plug in car ionizers” other review sites are pushing.
Once installed this is a 100 percent passive system. It doesn’t get much easier than that. All air that enters through your car’s HVAC is filtered. That can’t be said for any other purifier type.
This is a high quality HEPA filter that you would find in higher end purifiers. From a “how well it removes pollutants” perspective it’s a ten out of ten. However, you will see a bit of air flow reduction compared to a standard filter. But, that’s an understandable and acceptable compromise in our opinion. But, we do have to acknowledge that it does reduce fan performance and may put a little extra strain on your fan’s motor.
There are no moving parts and these filters are very well made. We’ve never experienced, or even heard of a failure. Short of an unheard of manufacturing defect… you’ll be fine with one of these filters.
This filter’s simplicity and use of an existing system in your vehicle keep costs down. There’s no motor, no case, no electrical controls. That means Bosch can put every penny into the filter and ultimately keep costs low. We’ve looked into a ton of car air purifiers and nothing in this price range even comes close.
This varys a lot by vehicle. However, you actually have to remove interior panels and such to even inspect or replace it. Compared to other purifiers this is pretty cumbersome. It’s not difficult or overwhelming… just a bit cumbersome.
Bosch is one of the best known names in the automotive industry. They make both original equipment and high quality replacement parts. That can’t be said for many other in car air purifiers. In fact the only one that comes to mind is Philips.
HEPA Cabin Filter Replacement
Bosch makes a replacement cabin filter for pretty much every vehicle on the road. Their standard filters are ubiquitous and filter out 90 percent of pollutants larger than 10 microns (your hair is about 50-70 microns in diameter). And, while that’s pretty impressive most of the things that can really harm you over the long term are in the sub-2.5 micron classification. In fact that’s why the EPA puts such an emphasis on PM2.5 pollutants. That’s also what Mr. Musk and his Tesla engineers are targeting with their high tech car purifier upgrade.
Beyond those tiny particles most OEM and even the standard Bosch units will do little to remove odor. Fortunately Bosch also make a line of activated carbon replacement cabin air filters. Other companies do as well, but Bosch is probably the most common. And, any filter with activated carbon will capture odors. But, like the standard models we mentioned above… they aren’t great at trapping fine particulate matter.
To capture PM2.5 you’ll need a HEPA filter. They’re government mandated to capture 99.97% of particles larger than .3 microns. That’s right… point tree microns folks. That’s a third of a micron. Or about 150-210 times smaller that the cross section diameter of a human hair.
If you live in a large city that’s really important. PM10 and Pm2.5 are pretty common in many major metros. Most of the particles come from things like combustion and construction. However, some of the most harmful actually occur in the atmosphere when two pollutants combine. Nitrogen oxides and sulfur dioxides are two common examples. You can always check local and regional air quality on sites like AirNow.gov. But, if you can see haze while you’re approaching the city on your commute… you need a HEPA filter.
Bosch Might not Make a HEPA filter for your Car
If you click on the image in the last section you’ll arrive at an Amazon listing for one of the Bosch HEPA cabin replacement filters. You should be immediately prompted to enter your car’s year, make and model… this will tell you if that particular part model is a fit.
If it doesn’t don’t worry there are between 20 and 30 HEPA filter part numbers Bosch offers for a wide variety of modern cars. Once you have entered your info into Amazon… it will remain and you’ll be notified if parts fit or not. From there you should be able to find out if Bosch makes a HEPA filter for your car. If you click on the following link you should see, on Amazon, a “filter by vehicle” option that will show you only the part numbers that fit your car.
If Bosch doesn’t make a HEPA filter for your specific vehicle there are other options. First, we’d recommend that you check to see if one of their activated carbon filters fit (here’s a list). Now those aren’t going to take care of Pm2.5 very well. But, they will capture about 80 percent of particles larger than 3 microns.
From there we would recommend looking into a Philips GoPure car air purifier. They have both an odor fighting filter and a true HEPA filter inside a fairly sleek housing. You will need to strap or mount it to a seat or console lid, but that’s about it. From there just plug it into a 12 volt socket and you’re good to go on the Pm2.5 fight.
“Ionizers” – Use with Caution
We could go on at length about ionizers, ozone, and the differences between them. But, when it comes to car purifiers we’re going to urge you to avoid anything that doesn’t mechanically trap particles. There is some truth to the application and efficacy of negative and positive ions in air purification.
However, a small dongle that you insert into a cigarette lighter (12V socket) isn’t going to magically purify the air in your car. It isn’t moving air. It can’t keep up with your car’s climate control system. It’s just not a feasible approach to… well anything.
Plus there’s a small chance that it will produce Ozone and possibly make cabin air quality worse. For more on ozone check out our ozone generator article, or visit the EPA’s website.
Pollution on the Road
When you hear about air pollution from transportation it’s almost always in reference to smog or global warming. While those are important, we think people are missing a huge problem common in transportation. That problem is in car exposure to VOC’s, particulate matter, and exhaust.
Some sources site that the air in your vehicle can contain 10 times more pollutants than even the air just off the asphalt. That’s pretty hard to wrap your head around. At least it is for us. We would think the air in the car would be about equal if not better than the air on the road itself.
But, if you stop and think about it for a while it starts to make sense. Air isn’t changing as quickly inside the cabin of your vehicle as it is on the road itself. Any VOC’s off gassing from your vehicle’s interior aren’t going to be much of a problem outside. And, things like brake dust, exhaust, and PM2.5 are basically being sucked into the car by your climate control system.
To be frank, we’re actually disappointed that HEPA filtration isn’t a standard feature in all modern vehicles.
So what can you do to limit your exposure? Well if you ‘ve made it this far you know a good first step is to buy a Bosch HEPA cabin filter. But, there are many other steps you can take to improve air quality in your car, truck or SUV.
Car Air Purifier Final Thoughts
We hope that eventually all searches for the best car air purifier will direct inquisitive consumers to our site. Or at least a review site that’s honest about air purification. There are too many sites out there who just list a bunch of purifiers and say they’re all “the best.”
But, the truth is; HEPA filtration is the only technology that really works well. It boasts a half century long successful track record in healthcare, defense, and commercial travel. HEPA is backed by scientific studies (like this one). They’re regulated by the government and were actually developed to purify air contaminated during atomic bomb testing.
Bottom line… get a HEPA filter for your car. If you commute (in traffic) you’re lungs are taking a beating almost each and every day. We replaced our filters with units from Bosch and think you should too.
1997 Study – Airborne pollutants along a roadside