Interdisciplinary Design Effort to Control Building Mechanical Equipment Noise

When locating a government building complex with its requisite power generating capabilities in a very quiet residential community, extensive interaction was required between the architect, mechanical and electrical engineers, and acoustical consultant. The success of the design was dependent on achieving acoustical compatibility with the neighborhood consistent with aesthetic, legal, and budgetary considerations. This case study is presented to highlight the interdisciplinary effort necessary to satisfy the various constraints imposed by the community, client, and designers. The maximum noise-level criterion established for the mechanical and electrical equipment was based on the existing ambient, and guidelines contained in U. S. Army Manuals TM 5-805-4 and TM 5-805-9. The noise levels of the air-cooled chillers, transformer, and engine-generator, all located in an outdoor equipment yard, were estimated using procedures elucidated in the Army manuals. This information was augmented by acoustic field measurements of similar equipment, plus manufacturers' SPL and power-level data. The noise-control treatments required to achieve the aforementioned acoustic criterion and their individual costs are discussed along with a description of the engineering modifications to the equipment.