After launching the world’s most cost-effective purifier (the Sqair), we started testing the HEPA lifespan. I’ve long been skeptical of the lifespan numbers purifier companies give because (1) they provide no empirical justification for the number and (2) they give the same numbers in Switzerland or Delhi. Yet clearly the HEPA would last less time […]
Category: Filters
Why a weaker filter actually makes a stronger purifier
Why does Smart Air’s latest air purifier, The Sqair, use a weaker filter–an H11 HEPA compared to the H12 and H13 HEPA filters out there? Tests of different filter grades revealed that weaker filters sometimes make stronger purifiers. Of course, purifier companies like to market their filters as top grade. Lots of purifiers […]
Can HEPA filters capture nanoparticles?
Many big purifier companies claim only their HEPA filters capture nanoparticles, like this Molekule ad. Although this claim is false, even journalists repeat this myth. Why is this belief so pervasive? One reasonable explanation is that the definition of “HEPA” leads people down that route. For example, this definition on Wikipedia […]
Can you clean a car air filter with compressed air?
Working on DIY air purifiers for over 6 years, I’ve heard from a lot of people who have strong intuitions about cleaning car air filters. People tell me they wash their vehicle’s air filter, vacuum it, or bang it really hard. Opinions are plenty, but what about real, hard data? Can you clean air filters […]
Hold on! Replacement filters cost more than buying a new air purifier?
Ever since Smart Air founder Thomas made his first DIY purifier, Smart Air has been telling the world that purifiers are needlessly overpriced. And ridiculously expensive replacement HEPA and carbon filters are one reason why. HEPA filters were invented over 70 years ago by the US government. There’s no patent, nothing fancy – they’re just […]
Can air purifiers kill dust mites?
Dust mites look scary. And apparently they’re probably in my home, since they’re in most people’s homes. A survey found dust mites in 84% of US beds and 68% of European beds. Yet it’s hard to know for sure whether they’re in our homes or not because they’re mostly too small to see […]
What is PM0.3 and Why Is It Important?
What does “PM” mean? PM stands for particulate matter–particles in the air. These particles can be solids (like dust) or liquids (like drops of water). Some common sources of PM are car exhaust, smoke from coal-fired power plants, pollen spores, and dust from construction sites. Sometimes you’ll see “PM” followed by a number, like […]
What combination of air filters do I need to protect against everything?
This will sound like a grand claim, but two filters are all you need. Here’s why (with data). Very Reasonable Reasons To Be Skeptical Why might you be skeptical? For one, big purifier companies are in an arms race to tell you they have more filters than the next guy. Simpleton Thomas here is […]
Smart Air Unveils New Techno-Ultra HEPA filter
This was an April fools post published on 1st April, 2019. The content of this article was published for the purpose of April fools – there is no fancy new tech in HEPA filters! Read on to learn why. “Finally, a HEPA filter that actually works!” Back when we started Smart Air in 2013, […]
How to Get the Most Out of Your Purifier
If buying an air purifier is the first step to breathing clean air, the second step is knowing how to use it best! Here are the 4 most important things to know about how to use an air purifier—based on data, not intuition. 1. Note down the date of purchase HEPA filters have a […]