Does White (or Pink or Brown) Noise Help or Hinder Open Office Workers?

By: Nancy Ordman

Colleagues’ chatter -- whether the noise comes from a phone conversation or what was once called water cooler schmoozing -- can cause reactions ranging from distraction to stress-inducing, productivity-busting irritation for those who work in open-plan offices. Since about 70 percent of U.S. offices have open plan designs, many employees could suffer the negative effects of indoor noise pollution.

The common remedy for open-office noise is to pump more noise into the environment. Paradoxically, this noise masks the intermittent conversations and other office sounds, providing a modicum of privacy to talkers and some relief from other auditory intrusions. This sound-masking sound comes in a range of colors, so called because the frequency and power of each chunk of the auditory spectrum sits on a continuum somewhat analogous to the spectrum of light.

Fighting sound with sound does damp down conversations. But does the interfering noise itself have a negative impact on office workers? For at least some people, the answer is yes.

Negative health effects of sound

Until the last 20 years or so, research on the deleterious effects of noise looked at many environmental sources: jet airliners taking off and landing, automobile traffic, the sounds of daily life that leak through thin apartment walls. Excessive exposure to very loud noise can cause hearing loss. Repeated exposure to other kinds of noise can elevate cortisol levels, which raises stress and interferes operations in the prefrontal cortex. Cortisol is the “fight or flight” hormone; perpetually elevated levels are damaging.

The power of noise to interrupt a train of thought has evolutionary roots. The brain analyzes each sound that reaches the ear and decides whether the noise is important in a life-or-death situation: Is a predator creeping up? Is a child crying? In today’s offices, the brain still has to sort through and classify sounds, labeling the important ones for conscious attention. Filtering noise and learning to tune out irrelevant sounds is tiring as well as distracting.

Does white (or pink or brown or violet) noise reduce negative effects?

Sound-masking sound works. Acoustical engineers have developed masking technology not only for open-plan offices but also for specific applications, such as eavesdropping prevention. However, some who work in environments with colored noise report that the background noise itself causes problems.

The National Institute for Occupational Safety and Health (NIOSH) says that some denizens of white-noise environments show the same kinds of stress, measured by cortisol levels, that people exposed to unremediated noise experience. Other negative health effects include hypertension, coronary disease, peptic ulcers and migraine. Some research indicates that stress might reduce dopamine availability in the prefrontal cortex, which, along with the increased cortisol, decreases brain function.

Researchers have investigated the effects that different colors of sound have on sleep for infants and adults, and attention and memory in schoolchildren and adults. Some studies look at whether white noise can mask the effects of tinnitus (ringing in the ears). No published research examines whether one sound color is better than another for masking or less likely to have the negative effects some have reported.

Coping with annoying sounds

For those whose work environment features annoying sound masking, what solutions exist? Noise-blocking headphones are a reasonable but pricey stopgap – not a solution – and they have downsides of their own. For those who need some sort of sound to help with concentration, dozens and dozens of varieties of sound apps run the gamut from white to brown noise to coffee-shop chatter to rain to waves hitting a beach. If the white noise supplier is willing to adjust the noise, a different combination of frequency and power might eliminate or greatly reduce the problem. Lucky people become habituated to the noise and no longer “hear” it.

Some people need silence to concentrate. Open-office designers are now more likely to create small, private workspaces large enough for one or two people to escape any color of sound permeating the office.