Return to Noise Assessment  Noise Assessment     Project Summary ::   1   2   3   4   5   6   7     Background The South Block project, developed by Dartmouth College, features a series of two, three, and four story buildings with an underground parking structure tucked undernearth. The project includes a mix of retail, office, and upper-story apartments. Project Scope After modeling, it was found that, without any mitigation, some of the larger fan units had the potential to exceed the local noise standard at the property line. RSG investigated designs to reduce these impacts including changes in equipment, active noise control, passive silencers, operating restrictions, equipment relocation, and acoustic louvers. After modeling several alternatives, new low-noise fans were specified, duct linings and duct silencers were incorporated, and acoustical louvers were installed. With this mitigation, the project was found to be in compliance with the zoning standard and a building permit was issued. Project Results Resource Systems Group conducted detailed computer noise modeling, which combined noise from several sources including highways and the proposed warehouse throughout the day and night. In this way, the times of greatest impact, as well as the highest overall noise levels, were determined for locations outside the property. Compliance with local noise statutes and federal guidelines was insured by modeling the optimum location for a noise barrier which mitigates impacts at a nearby residential area. The noise control barriers at the proposed southern site will reduce noise levels at nearby residences by up to eight decibels.