The purifier runs very quiet. I purchased this larger model for our shop.. and seems to be working properly. The light indicators on the lid visually show you the quality of air flowing through it.. and out. It doesn't take up much space.. and is easy to move around to other locations in our shop. I am actually quite pleased with it.
 I was hoping it was 100% made/built in the USA.. considering the price.. that's what I thought.