The Challenges of Working with Vendor-provided Noise Data During Community Noise Propagation Modeling and Process Equipment Bid Submittal Evaluations

During a project design phase that involves community noise limits, it is common for design-construct firms to include a request for equipment noise data with their bid documents. The prospective equipment vendor noise data request frequently seeks the spectral frequency sound power levels. Projects often involve the main process equipment as well as the balance-of-plant or ancillary equipment. The main process equipment vendors may respond with the requested spectral sound power level data, spectral sound pressure level data for a certain distance or for a specific radiating surface area, or just an overall A-weighted noise level at a specific distance, e.g. 400 feet, for their equipment portion of the project. This typically excludes the balance-of-plant equipment, unless vendors are asked to bid on a turn-key basis. Otherwise, similar data requests are made of the ancillary equipment vendors. Thus, the project's noise modeler is challenged to develop a fair assessment of the vendor-submitted noise data included with their equipment bids. This paper presents comparisons with various normalized vendor-submitted noise data for a simplified power plant noise model to demonstrate the challenges and difficulties encountered during the bid submittal evaluation process.