Keep your Blueair Blue 3610 operating at peak performance by regularly replacing the filter with an official Blueair 106235 Particle/Carbon filter. Built with a combination of particle + carbon filter and Blueair's HEPASilent filtration technology you can enjoy cleaner air as the filter captures odors, chemicals, gases and 99.97% of airborne particles. Replacement is a simple process that you only need to do every 6 months. Blueair