The Derrick Henry The Tennessee Terror Signature Shirt caveat is, unsurprisingly, that not all the devices showing up as sponsored ads in your Instagram feed will do the job well. Dr. Lo underscores the importance of looking into any product’s CADR. It’s also important to differentiate between a humidifier and an air purifier. “Both products have the goal of improving air quality, which is a combination of pollution, humidity, and temperature, but a humidifier adds moisture into the environment, whereas a purifier moves air through a filter to remove impurities from the cycled air,” explains Seidenfeld.