The World Health Organization recommends ambient noise ≤35 dB for sustained cognitive work environments. WELL Building Standard v2 sets a similar threshold. At this level, irrelevant speech from outside the space becomes inaudible, eliminating the involuntary language processing activation that is the primary mechanism of focus disruption. HIGHKA pods achieve approximately 30 dB inside the pod from a typical 65 dB open-floor ambient — meeting or exceeding this threshold.