Aside from chips and sawdust, woodworking creates almost invisible dust particles that leave a messy residue on everything in the shop. Even worse, that residue can create sinus symptoms and allergies, and lead to serious lung problems. This 3-stage filtration system completely changes the air in a 20' x 20' x 8' room six times an hour - protecting counters, work surfaces, and drying finishes from settling dust; removing wood, ceramic, plaster and drywall dust. It substantially reduces clean-up, stops dust drift, and most importantly it helps protect your health. A PureAir System is the best shop investment you can make.