: Every doubling of the sone value corresponds to a doubling of perceived loudness.
The term "sone rating" is most frequently encountered in for household ventilation, particularly bathroom exhaust fans. Bathroom Fan Ratings sone rating scale
As urbanization increases and homes become multi-functional offices, the tolerance for mechanical noise is dropping. Regulatory bodies are even beginning to use Sones in building codes; for example, the U.S. Department of Housing and Urban Development (HUD) often sets limits on noise levels in Sones, not decibels. : Every doubling of the sone value corresponds
Historically, manufacturers relied on decibel ratings to hide noise levels. A "quiet" appliance might have a low overall dB rating, but still emit a high-pitched whine that human ears are particularly sensitive to. Because the decibel scale doesn't weight frequencies the way our ears do, the numbers didn't match the annoyance. Regulatory bodies are even beginning to use Sones
