You can set the fan to low or high, or for whisper quiet, choose the special sleep mode.

Promising review: “I bought these during the CA wildfire season of 2020 and put them in my kids’ bedrooms. While we live at least an hour from the closest fire, our air was at a hazardous level for days the sky was red and smokey. The kids stayed indoors since school was closed due to health risks from the smoke and the air was hazardous but both started to cough and my youngest’s allergies were horrible. I put them in their rooms on high and they had a bit of relief until the air cleared. They work well and are relatively quiet, in the high mode, it’s substantially louder but it turns into white noise. 

Once the air cleared and we continued to use the air purifiers, I noticed my youngest daughter’s allergies, which got worse at night, were much better. Her worst allergy is to dust mites and while we put up stuffed animals, and put the mattress and pillow covers to eliminate dust mites, she would still have issues. The air purifier has substantially helped her sleep better and seems to help give her relief when her seasonal allergies flare up, it’s not so bad in her room. It’s not a miracle cure by any means but it has been the difference in lowering the number of nights she is up sniffling, sneezing, and miserable.” —Katie

Price: $99.99 (originally $175.09)

Source: https://www.buzzfeed.com/cierracowan/all-the-best-fourth-of-july-deals-at-amazon