Blueair Replacement Parts. Blueair requires a filter change every 6 months to ensure your Blueair Air Purifier is working at peak performance and to uphold there extensive warranty. All Blueair Filters are interchangeable so if you orginally purchased a basic air purifier with the standard Particle Filter, you can always choose to upgrade to a Smokestop Filter. If you need further clarification, do not hesitate to call!