HVI - The Home Ventilating Institute is the trade association of residential ventilation product manufacturers. HVI was founded in 1955 and created the Certified Rating Program to "provide a fair and credible method of comparing ventilation performance and noise levels." A random verification program ensures that Certified products perform as advertised. The Comfort Stream was tested at the Texas A&M Energy System Laboratory for both air flow and sound level. At present there is no certification of sound level for remote, in-line fans, but the Comfort Stream's sounds at the grilles (just 1.9 sones much quieter than the majority of bath fans) was tested using a standardized set up. If the product is "HVI Certified" you can be sure that it will perform as described.
That's important.
