Acoustical design of heathcare facilities for leadership in energy and environmental design green building certification: Odd harmonic filter for mechanical system noise control.

Abstract

To achieve the leadership in energy and environmental design (LEED) indoor environmental quality credit 2: acoustic environment, healthcare facilities must meet stringent sound and vibration criteria. Mechanical system noise presents one of the largest obstacles to meeting the room noise design requirements. Code requirements intended to promote indoor air quality, and infection control limits the use of typical absorptive materials such as fiberglass duct liner, packed duct silencers, and other porous absorbers. Energy code requirements force mechanical system designers to locate large noise sources such as air handlers, fan‐powered terminal air boxes, and exhaust fans close to the spaces they serve, adding to background noise levels. One innovative, practical solution to tonal mechanical system noise is an odd harmonic filter. Acoustical performance of odd harmonic filters and strategies to achieve the room noise criteria for the LEED acoustic environment credit will be discussed.