GUIDES17 min readFeatured
NRC 0.75 Does Not Mean 75% Absorption — Here Is What It Actually Means
NRC is an arithmetic average of four octave bands. A panel rated NRC 0.75 can have α = 0.40 at 250Hz — and that bass deficiency will make your meeting room fail its WELL F74 assessment at the exact frequency where speech intelligibility lives.
March 13, 2026NRCabsorption coefficient