Work group narrows noise rules, drops controversial L90 standard

Presenter (speaker 1) told the group he had removed one of the measurement standards (the L90 one‑hour metric) after feedback that it was difficult to measure and vulnerable to transient spikes. "So the feedback I got was it's hard to measure and it's kind of overly what's the word that was used? It's overly regulatory to do it. So I took it out," he said.

Instead of 24/7 continuous monitoring, the draft calls for interval monitoring with records retained by the applicant; the area plan office will request records and may perform independent monitoring if complaints arise. The ordinance retains multiple shorter‑interval metrics (A‑weighted and C‑weighted every 10 minutes), discrete‑tone measurements across bandwidths, and a low‑frequency 15‑decibel offset to address ground and low‑pitch noises. The changes are intended to balance enforceability, privacy concerns and technical feasibility.