騒音 criteria (nc) curves と indoor 騒音 levels

Nc rating システム for indoor background 騒音, recommended nc levels for various building spaces.

noisecriteriacurvesデータ表

Overview

Engineering reference data for Noise Criteria (NC) Curves and Indoor Noise Levels in acoustics.

$c = \sqrt{\gamma R T}$

Speed of sound in an ideal gas.

$L = 10 \log_{10}(I/I_0)$

Decibel level.

$\lambda = c / f$

Wavelength = speed / frequency.