INTENT
The WELL Sound concept aims to bolster occupant health and well-being through the identification and mitigation of acoustical comfort parameters that shape occupant experiences in the built environment.
BACKGROUND
The acoustical comfort of a space can be quantified by the overall level of satisfaction of an occupant in a given environment.[1,2] The word “sound” itself is generally defined as the human response to mechanical vibrations through a medium such as air. By this definition, human perception of sound is paramount in shaping a sonic environment. Only in recent years has it been determined that exposure to noise has been shown to hinder the health and well-being of people in a number of different ways.[3] For instance, the effects of exterior noise from transportation or industrial sources have been linked to sleep disturbance, hypertension and the reduction of mental arithmetic in school-aged children.[4-8] A number of studies have also indicated that internally generated noise is a major cause of complaint and ultimately results in occupant dissatisfaction.[1,9-12] Sound within an enclosed space from sources such as HVAC equipment, appliances and other occupants has been shown to hinder productivity, focus, memory retention and mental arithmetic.[8,10,11,13-16] In addition to airborne noise sources, impact noise from adjacent activity such as footfall, exercise or mechanical vibration can create uncomfortable environments for occupants in receiving locations.[13,17] Another common acoustical issue is the overall level of privacy within and between enclosed spaces. For instance, research has indicated that occupants are generally dissatisfied when conversations can readily transmit between rooms or across an open office, thus hindering confidentiality or creating distraction from tasks.[18] Inappropriate reverberation times and background noise levels in a space can impede speech intelligibility and cause strain for occupants who may possess hearing impairments.[19-22] Speech intelligibility is also a crucial element in educational facilities where information is being presented to large audiences and aural comprehension is vital for memory retention and task completion.[23] With the rise in hearing impairments and various other health concerns as a result of over-exposure to noise, designing a single space to meet the acoustical comfort needs of every individual is challenging. However, existing research into the effects of best-practice acoustical design within a space suggests that a holistic approach to addressing the issue of acoustical comfort in the built environment is achievable.[11,13,24] The planning and commissioning of an isolated and balanced HVAC system provides a firm baseline for the anticipated background noise level in a given enclosure.[13] The fortification of façade elements can ensure that exterior noise intrusion is subdued much to the benefit of occupant comfort during work, study or sleep.[4,6,25-30] Adding mass and glazing to partition elements, sealing gaps at connections and doors and providing airspace between enclosed spaces bolsters sound privacy and increases occupant comfort.[29,31,32] Replacing areas of hard surfaces in a space with absorptive materials can reduce reflected sound energy and better facilitate acoustical privacy or, conversely, improve speech projection.[19,24,33,34] Consistent background noise levels can be introduced into a space using a sound masking system, thus improving the signal-to-noise ratio in favor of acoustical privacy between occupants.[12,35]
WELL aims to provide a comprehensive and holistic approach to addressing the concerns of acoustical comfort through research-based design considerations that buildings can accommodate for the purposes of improving occupant health and well-being.
SOUND FEATURES
Feature S01
Sound MappingPRECONDITION
Incorporate strategic planning and mitigation required to prevent general issues of acoustical disturbance from both externally and internally generated noise.
Feature S02
Maximum Noise LevelsOPTIMIZATION
Establish background noise level criteria for enclosed spaces in order to promote best-practice HVAC and façade design techniques and ultimately bolster acoustical comfort within.
Feature S03
Sound BarriersOPTIMIZATION
Increase the level of speech privacy between horizontally adjacent enclosures and highlight design constraints that may hinder acoustical comfort.
Feature S04
Sound AbsorptionOPTIMIZATION
Design spaces in accordance with comfortable reverberation times that support speech intelligibility and are conducive to focus.
Feature S05
Sound MaskingOPTIMIZATION
Increase acoustical privacy in open workspaces and between enclosed spaces.