2025 02 03 Acoustical Evaluation

PN Restaurants -4- 3 February 2025 4.0 ACOUSTICAL EVALUATION AND RECOMMENDATIONS The evaluation of the sound pressure levels due to the operation of the proposed equipment was based on the manufacturers’ sound pressure level data for the typical restaurant mechanical equipment and drive-thru intercom system, as well as sound data from LSG&A’s database for typical car and truck operations. To calculate the sound pressure levels at the adjacent properties, an acoustical model was developed that considered the propagation of sound over distance, the shielding and reflection of sound due to buildings, the effect of topography, and the effect of air and ground absorption. Attenuation due to foliage was not considered. The modeling was performed using SoundPLAN software and the calculation methodology outlined in ISO Standard 9613-2. 4.1 Fence LSG&A understands that a 6 foot tall solid vinyl fence is proposed at the south and west sides of the site. Care must be taken to ensure that the seams are tight with no gaps. This fence has been considered in the acoustical model. 4.2 Intercom System The acoustical model included one intercom at the drive-thru. LSG&A recommends that the intercom system include automatic volume control (AVC) which restricts the output to 15 dB above the ambient sound level, such as those by HME. Based upon the measured ambient sound levels and typical sound levels from idling cars, LSG&A estimated the intercom loudspeakers to have a sound output of up to 76 dB(A) at 1 foot from each loudspeaker. 4.3 Rooftop HVAC The following rooftop equipment and associated manufacturers’ sound data was included in the acoustical model for each restaurant, assumed to be located towards the middle of the roof.  Two Rooftop Units (RTU) – 82 dB(A) sound power level  Two Kitchen Exhaust Fans (KEF) – 76 dB(A) sound power level  One Bathroom Exhaust Fan – 65 dB(A) sound power level