Blueair’s Sense+ Filter also features: Electrostatic cling: Airborne particles pass through a chamber to get electrically charged before passing through the gradient structure of our filters. The charge causes the polluted particles to effortlessly adhere to the filter media, capturing even fine particles such as tobacco smoke. Traps particles for good: The Sense filter’s progressive structure acts like many filters in one, trapping particles in a range of sizes while maintaining maximum airflow. The gradient structure resists clogging and will never re-release particles back into the air, even when the filter is heavily loaded. Environmentally friendly: We designed our filter media to be less dense, meaning our filtration system requires lower air pressure and lower energy consumption. The Sense filter is 100% recyclable, so the only thing you’re adding back into the environment is clean air. Blueair recommends changing your filters every 6 months to maintain optimum indoor air quality.