Calculating CADR with airflow and filtration %

How to Calculate CADR From an Air Purifier’s Airflow

CADR tests, used to calculate an air purifier’s effectiveness at cleaning air, are typically used to compare the performance of different purifiers. However, performing a CADR test is not simple: it requires a particle monitor, a sealed 30m3 test lab, and tightly controlled testing conditions. Because of the complexity of …

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What’s CADR and What’s the Difference With Airflow?

When buying an air purifiers, the terms ‘airflow’ and CADR are often used interchangeably to describe an air purifier’s performance. But what’s the difference between CADR (clean air delivery rate) and airflow? Are they the same thing? Or which one – CADR vs. airflow – should be used when buying …

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Dyson Pure Cool air Purifier Tower CADR Review

Dyson Pure Cool Air Purifier Review: Shockingly Bad

Dyson’s Pure Cool air purifier looks impressive. However a review of its clean air rating (CADR) reveals this filter does a poor job of providing clean air – the Dyson TP05 Pure Cool’s CADR comes in at just 164m3/hr. That means the Dyson Pure Cool air purifier out as much …

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How’s the Air Quality in Tangshan?

There are reasons to be pessimistic about the air quality in Tangshan. Tangshan is a largely industrial city in Hebei province, which is the industrial heartland of China and one of the most polluted provinces. Tangshan also boasts one of China’s top 10 busiest ports.     To get some …

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New DIY Purifier Design Increases CADR 15%

After I made my first DIY purifier, a design magazine called me up to interview me. I said, “You realize this has no design in it, right? It’s just a fan and a filter.” Now I actually have a design improvement! I’m calling it the DIY 1.1.  The Problem The …

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New DIY Design Increases CADR 15% – Supplemental Data

Methods Results were identical to my earlier tests of the Original DIY, Blue Air, IQ Air, Xiaomi, and Philips. Anna conducted the overnight tests in her 15m2 Beijing bedroom. Doors and windows were closed during the test (except for occasional opening during the first couple hours before bed—that random variation …

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Smart Air low cost purifiers

Smart Air is a social enterprise and certified B-Corp that offers simple, no-nonsense air purifiers and provides free education to protect people from the harms of air pollution. We are proud to be the only certified B-Corp dedicated to fighting air pollution.

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