Workgroup tightens noise monitoring standards for proposed county data centers

Staff member walked committee members through a multi-factor noise standard the draft now includes: a 10-minute averaging interval, an LA90-style approach that discards the top 10% of spikes, an A-scale vs C-scale separation threshold, and octave-band analysis to detect prominent discrete tones. "I lowered it to 10 minutes... the 90% LAQ that I put in measures still measures it over that hour, but it throws out the highest 10% of the spikes," the staff member said.