Decibel (dB) Sound Level & Inverse-Square Distance Attenuation Calculator
Calculate sound pressure level in decibels (dB) at any observer distance, sound attenuation loss, and acoustic intensity drop under inverse-square spherical wave propagation.
Calculator Inputs
Live Real-TimeSound Level at Observer (L₂ in dB)
Sound Level Attenuation (ΔdB)
20 dB
Distance Multiple (r₂ / r₁)
10 x
Auditory Safe Zone: Distance attenuation reduced sound pressure below the 85 dB occupational hazard threshold.
Decibel Attenuation Profile
Detailed Calculation Breakdown
Calculation Methodology
Inverse-Square Acoustic Formula: L2 = L1 - 20 * log10(r2 / r1). Sound level decreases by approximately 6 dB for each doubling of distance from a point source.
Important Legal & Educational Disclaimer
This acoustic physics tool calculates free-field geometric sound attenuation.
This calculator is designed for educational and informational purposes only based on public statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimations. Always verify with the relevant official authorities or a certified professional advisor.
Frequently Asked Questions
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