The EcoQuest Air Purifier features a 5 speed fan that can be a bit loud and irritating for some people. However, many are willing to overlook this as the EcoQuest is excellent in removing airborne particles. The EcoQuest has a UV lamp that indicates if there are bacteria in the air or not. For users who don’t want to get into measuring bacteria in the air or whatever, they are completely satisfied with letting EcoQuest Air Purifier do its job. The EcoQuest Air Purifier has an active timer that enables users to run the unit up to 6 hours uninterruptedly. It also has an automatic system that sends out alarms if there is a need to replace filters or clean the unit.