Because dBA is logarithmic and Sones are linear, there is no single perfect formula that works for every frequency. However, the industry-standard "rule of thumb" for a 1kHz tone is: Common conversions usually look like this:
≈ 28–30 dBA (Whisper quiet; typical for high-end bathroom fans) 2 Sones ≈ 38–40 dBA (Quiet office noise) 4 Sones ≈ 48–50 dBA (Standard conversation) 3. What Does "Verified" Mean?
Look for the HVI Certified or AMCA label on the box or spec sheet. sone to dba verified
If you are an architect, contractor, or DIYer, seeking verified ratings is crucial for several reasons:
In commercial and residential construction, "verified" usually refers to or HVI (Home Ventilating Institute) certification. When a product is "Sone to dBA verified," it means: Because dBA is logarithmic and Sones are linear,
Unverified products often use "marketing dBA," which might be measured from further away or in "ideal" settings that don't reflect real-world use.
Sound was measured at a specific distance (usually 5 feet or 1.5 meters) to ensure consistency. Look for the HVI Certified or AMCA label
This is a linear unit of "perceived loudness." It was designed to be more intuitive for the average person. For example, 2 Sones is exactly twice as loud as 1 Sone. 2. The Rule of Thumb for Conversion
Many modern green building codes (like LEED or WELL) require ventilation fans to stay under a specific Sone level to ensure occupant comfort.