Wildfires can result in dangerously high levels of air pollution. Thus it is important to be prepared and know how to protect yourself from the wildfire smoke. Wildfire smoke contains dangerous small particles (PM2.5) that can cause serious health effects. So the next time there is a major wildfire (i.e. California), how can you protect […]
Category: Filters
Recent Filters Articles:
Can Activated Carbon Remove Formaldehyde?
Can activated carbon filters remove formaldehyde and VOCs? Earlier tests from Smart Air found that carbon can reduce VOCs from cigarette smoke. But formaldehyde and VOCs in general are particular concern for many people. We put activated carbon filters to the test by ordering formaldehyde straight from the factory and testing it against carbon filters. […]

What Are HEPA Filters and How Do They Work?
The term “HEPA filter” can be confusing. What does HEPA stand for? What is a HEPA filter made from, and what actually makes it a HEPA filter? What Is a HEPA Filter? “HEPA” stands for “high-efficiency particulate air” (filter). It sounds complicated, but HEPA air filters are nothing fancy. They were invented back in the […]

Can HEPA Filters and Air Purifiers Capture the Coronavirus?
Data shows face masks can protect you from the coronavirus, but how about air purifiers? How effective are HEPA air filters at capturing the coronavirus? Can HEPA Filters Capture and Remove The Coronavirus? To answer this question, we need to first answer if HEPA filters can capture particles as small as the coronavirus. The COVID-19 […]

$70 DIY Purifier Effectiveness Better than $1,000 IQAir
New head-to-head test data from a citizen scientist finds that a simple, taped-together DIY purifier effectiveness is higher than a market-leading Swiss purifier. This data adds to an accumulation of data suggesting that the effective air purifiers need not be expensive. The Setup The underlying science of purifiers is simple: purifiers are just fans and […]
How to Clean and Wash HEPA Filters? Here’s Why You Shouldn’t
Can you wash a HEPA filter? If so, how should you wash or clean a HEPA filter? These questions keep cropping up, as they’re just about the only remaining problem for HEPA filters. HEPA filters are almost perfect: they are backed by tons of scientific tests; they’re pretty cheap; they use about as much energy as […]

Why Air Purifier Pre-Filters May Be More Harm than Good
Most purifiers on the market come with a pre-filter. That would make one think that pre-filters must be a good thing, right? However, most purifier companies also love to selling people 6-stage filtration, or no – 7-stage filtration! But the science behind purifiers is surprisingly simple. Two types of filters will protect you against […]
Why are Air Purifiers so Expensive?
I thought about why air purifiers cost a lot because I was living in Beijing when the (first) “airpocalypse” struck. Here’s what it looked like: The High Price of Air Purifiers I went out to buy an air purifier, and found that the one I wanted cost $2,000! I worked out I’d need two for […]

How Long Does a HEPA Filter Last?
“How long does a HEPA Filter last?”. “How often should I replace my HEPA Filter”. These are two common questions I got asked when I started teaching people how to build air purifiers. Rather than just give people a nice-sounding answer, I wanted to see what the data says, so Smart Air co-founder Gus has […]

Can HEPA Filters Be Used to Make DIY Face Masks?
News media like The New York Times and Today have been talking about using HEPA filters as a material to make DIY face masks. There are even YouTube videos showing how to DIY a mask out of a HEPA filter. But just how well can HEPA filters capture virus-sized particles, and can HEPA […]
