Partially true. A batch verification (code 318) applies to a specific production run. Reputable manufacturers continuously re-verify. If a product was last verified in 2015 and the design changed in 2022, the old "318" code is invalid. Part 7: The Cost-Benefit Analysis of Insisting on Verification | Aspect | Non-Verified Product | Sone 318 Verified Product | | --- | --- | --- | | Initial cost | $30 – $80 | $80 – $250 | | Noise consistency | ± 2 sones | ± 0.2 sones | | Code compliance risk | High (often fails inspection) | Low (universally accepted) | | Customer satisfaction | 50% | 95%+ | | Warranty support | Unclear testing basis | Backed by test report |
means a third-party, accredited laboratory has tested the product according to strict international standards—most notably ASTM E2779 (Standard Test Method for Determining Sound Power Levels of Fans) or ISO 3744 . sone 318 verified
Long-term value: A verified fan lasts 10–15 years. The extra $100 upfront saves hundreds in callbacks, complaints, and potential drywall work to replace an unverified noisy unit. If you are writing a specification, use this exact language: "Provide exhaust fans that are HVI-Certified (Home Ventilating Institute) with sound levels verified per ASTM E2779. The fan model shall display a Sone 318 Verified label or equivalent third-party certification indicating that the maximum sound output does not exceed [insert number] sones at 0.1 in. w.g. static pressure and rated CFM. Submit test report with certification number containing '318' or newer batch reference." This language protects you against substitutions. Part 9: Future of Verification – Beyond 318 The industry is moving toward even stricter standards: "Sone 500 Verified" and "Sone 0.0" for passive ventilation systems. However, as of 2024-2025, Sone 318 Verified remains the most widely recognized shorthand for trust in acoustic performance. Partially true