Broan-Nutone Air Purifier Replacement Filter The Easy-To-Replace. 3-Stage Filter For Broan-Nutone Air Purifier Bnap-100 Captures Pollutants As Large As Pet Dander And As Small As A Virus. The Mesh Filter Stops Large Particles Such As Fabric Fibers While The True Hepa Filter Captures 99.97% Of All Particles Down To Respiratory Droplets And Viruses. And This Filter'S Activated Charcoal Captures Harmful Tvocs (Total Volatile Organic Compounds) Such As Cleaning Chemicals.