Methodology

Data source

All sound levels on QuietScore come from the ENERGY STAR Certified Ventilating Fans dataset published as open data by the U.S. Environmental Protection Agency. To earn certification, every product is tested to the Home Ventilating Institute (HVI) sound procedure in an accredited laboratory and its loudness is reported in sones. These are measured values, not manufacturer marketing claims, and the same test procedure applies to every model — which is what makes cross-brand comparison meaningful.

What we compute

• Rankings and percentiles — each model is ranked against every other certified model in its category.
• Approximate dBA — converted from sones using dB ≈ 40 + 10 × log₂(sones), always labeled approximate. Details and caveats here.
• Room sizing — bathroom fan suitability uses the HVI guideline of 1 CFM per square foot.
• Deduplication — when the same brand and model number appears in multiple certification rows, we keep the most recent certification.

Freshness

An automated pipeline re-fetches the EPA dataset weekly, adds newly certified models, flags spec changes, and rebuilds the site. Every model page shows the date its data was last fetched. If an upstream fetch fails, the site keeps serving the last verified data rather than guessing.

Limitations, stated plainly

• The database covers ENERGY STAR certified models. Uncertified products (including many cheap and many premium models) are not yet listed.
• Range hood sones are measured at the test speed defined by the certification procedure; maximum-speed noise will be higher.
• Real-world loudness also depends on installation: duct runs, mounting, and resonance can add noise no spec sheet captures.

Corrections

Spot an error? Every number links to its official source so you can verify it. If the source disagrees with our page, the pipeline has a bug — contact us via the address on the about page and it gets fixed.