As the industry leader in Indoor Air Quality, Healthy Air Professionals everywhere turn to AprilAire for everything needed to test and mitigate radon in homes. All Aprilaire fans are UL and CUL approved for residential, commercial, and industrial use. The fans are backed by a 5-year full replacement warranty. They are widely recognized as great-quality fans that are built to last and offer excellent performance as well as efficient operation at a reasonable price. MUST HAVE A LOG IN TO PURCHASE. OR CALL 888-800-5955.