Sone - 363

A: Absolutely not. A 363-sone fan would be 125 dB—louder than a live rock band. It would shatter glass and cause immediate hearing loss. Residential bathroom fans are 0.3 to 2.0 sones.

A civil defense siren rated at 125 dB @ 100 feet translates to roughly 363 sones at the source. This is the legally mandated minimum for tornado sirens in many US jurisdictions to ensure wake-up effectiveness. sone 363

| Effect | Threshold (approx.) | Relevance to 363 Sone | |--------|---------------------|----------------------| | Temporary Threshold Shift (TTS) | >85 dB for >8 h | 363 sone (≈125 dB) causes TTS within minutes. | | Permanent Threshold Shift (PTS) | Cumulative exposure >100 dB | A single 363‑sone event can produce irreversible damage if the duration exceeds a few seconds without protection. | | Acoustic Trauma (ruptured eardrum) | >150 dB SPL (instant) | 363 sone is below the rupture threshold but can cause severe pain and disorientation. | | Startle and Stress Response | >110 dB SPL | The autonomic surge (adrenaline, heart‑rate spike) is typical near 363 sone sources. | | Masking of Speech | >70 dB SPL | At 363 sone, normal conversation is impossible without shouting or electronic amplification. | A: Absolutely not

The non‑linear nature of hearing damage means that each additional decibel above 85 dB roughly doubles the risk of injury. Consequently, a sound at 125 dB (363 sone) is orders of magnitude more dangerous than a typical city street (≈60 dB, 1 sone). | Sound Source | Typical Sones | dB SPL (approx

| Sound Source | Typical Sones | dB SPL (approx.) | |--------------|--------------|------------------| | Breathing | 0.1 | 10 | | Quiet library | 1 | 40 | | Normal conversation | 4 | 60 | | Vacuum cleaner | 8 | 70 | | Chainsaw (1 meter) | 64 | 110 | | Sone 363 | 363 | 125 | | Jet takeoff (100m) | 512 | 130 | | Firecracker (1m) | 2048 | 150 |

Verdict: 363 sones is dangerously loud. Without hearing protection, permanent damage occurs in minutes. Products at this level are strictly industrial or military.