One person's sound is another person's noise. Take the much-maligned cell phone. We all complain about other people's annoying ring tones or being subjected to everyone else's chatter—except when that person is ourself. Then chatter becomes conversation. We all want to be free of unwanted sound, which we call "noise," and, at the same time, conduct our business as we see fit. There's the rub, but what can we do about it?
Thanks to advances in acoustical research and cognitive psychology, one of the things
we can do as designers of interior environments is better understand how occupants respond to the acoustical characteristics of a space. For a particular environment, when is sound just sound and when does it become noise? One might reasonably assume
that loudness and clarity are important factors, but one would only be partially right. Human beings handle various degrees and types of noise pollution in different ways. Even within the same space a particular level of noise will be quite acceptable at one time, but at other times the same level becomes unbearable. This is true in the home environment as well as the work environment.
Incorporating furnishings and technologies designed to absorb, muffle or mask unwanted sound can be highly effective, but these measures address only part of the problem. For aside from the "objective" acoustical qualities of a space, we must consider what preferences and expectations the intended occupants are likely to bring with them into
the environment we design. The evidence suggests that personal perception plays a major part in how individuals assess the quality of the acoustical environment. For example, an ASID survey of nearly 400 office workers found that acoustics is a significant factor affecting workers' sense of their levels of productivity, comfort and job satisfaction. However, workers accustomed to open plan offices were less likely to perceive acoustics as an issue as were workers accustomed to having a private office.
A number of different factors come into play when we take into consideration not just the number of square feet that a worker occupies, but also the purpose of the work and the temperament of the people who perform the work. It does not take much investigation to recognize that specific occupations or tasks require a greater or lesser need for acoustical privacy. Nonetheless, individual workplace environments have continued to shrink and workers are being "reorganized" into open plan spaces, regardless of their roles and responsibilities. As employers seek to maximize the use of valuable floor space, how has it impacted productivity, absenteeism and employee turnover?
The combination of other stimuli present can also affect how occupants perceive the acoustical quality of a space. In one study, workers who could see their colleagues talking were more likely to complain of a lack of aural privacy than workers who could not, even though the audio and intelligibility level of the conversations stayed the same. On the other hand, a lack of other types of stimuli can cause one sense to dominate and become more acute. Many of today's work environments are so controlled that visual, tactile and olfactory stimuli become neutralized, leaving hearing as the sense most stimulated by
the environment. In a project recently completed for the U.S. Environmental Protection Agency, the designers did their job of ensuring acoustical privacy so well that employees complained that their offices were too quiet, causing them to become sensitive to every creak and squeak in the building. A sound masking system was installed to add background noise and thus better balance the level of sensory input.
How occupants expect an environment to sound also colors how they are affected by that environment. We expect sports stadiums and rock concert arenas to be loud, so we tolerate the intense level of sound. At work, we may not register the hum of conversation in the cafeteria, but will consider our work space to be noisy if it reaches the same level of activity.
These "subjective" factors become more complex when we address individual needs as well. We know that ambient sound can agitate, distract and even disorient workers experiencing hearing loss, and thus most likely affect the productivity and well-being of those employees. When we consider that some degree of hearing loss is common for most people beginning in their early '40s, usually involving increased sensitivity to ambient sound, how are we to reconcile these physiological changes with the current trend toward more open and compressed working environments?
Traditional programming can only take us so far in creating solutions to address this web of interrelated issues. As the authors of a new ASID professional paper on office acoustics point out, occupants often lack an understanding of or are unable to articulate what it is they are responding to in the environment. By applying the tools of occupancy research and building performance management, we can not only better understand how and why occupants respond to different environmental configurations, but we can establish methods and measures to demonstrate the value that good design brings to the bottom line over the lifetime of a building by contributing to the productivity and well-being of the workers.
Linda Elliott Smith is president of education-works, inc. in Dallas, TX, and serves as president of ASID. She has served the society in a number of volunteer positions for more than 20 years. ASID can be reached at (202) 546-3480; fax: (202) 546-3240; www.asid.org.