Noise measurement rules and nighttime limits

(a) The department shall adopt rules in accordance with chapter 91 that shall use both the dBC and the dBA sound level measurement systems for community noise control. The department and the county liquor commissions may enforce nighttime noise levels in any urban land use district measured from over fifty to sixty decibels, measured using the dBC weighting system, in certain areas they deem appropriate and not adversely affecting public health and safety. (b) In any urban land use district, a sound level of more than sixty decibels for bass sound (using the dBC weighting system), measured at a complainant's site, shall be deemed to exceed the maximum permissible sound at nighttime; provided that, where the complainant's site is within or in close proximity to an area zoned mixed-use or residential, the maximum permissible sound at nighttime shall be fifty decibels dBC. (c) For purposes of this section: "Nighttime" means the time between the hours of 10:00 p.m. and 7:00 a.m.; and "Urban land use district" means property designated as such pursuant to section 205-2. [L Sp 2009, c 25, §3]