OfficesResearchUS University study finds ‘Café-like noise levels’ ideal for office spaces

We process sound continuously throughout the workday, with different spaces providing varying noise levels. Is one noise level better than another? New research from the University of Arizona and the University of Kansas reveals that “coffee shop” noise levels might offer the most well-received solution.

There are two extremes to noise: overwhelmingly, and sometimes painfully, loud sound and then the quiet we might experience in a library. Anything too loud can be distracting and irritating, but too quiet can have the same problem. Inclusive design offers different design options for sound levels, but is there a range that is generally suitable?

The University research found that the ideal amount of noise in healthy offices is around 50 decibels – which is roughly the same as the pitter-patter of moderate ran on the roof or to bird song. Research showed that stress levels were significantly higher when sound was both above and below this threshold.

“Everybody knows that loud noise is stressful, and, in fact, extremely loud noise is harmful to your ear,” said study co-author and physician Prof. Esther Sternberg, director of the University of Arizona Institute on Place, Wellbeing and Performance in Tucson. “But what was new about this is that with even low levels of sound – less than 50 decibels – the stress response is higher.”

Experimenting with sound levels

The study, “Discover of associative patterns between workplace sound level and physiological wellbeing using wearable devices and empirical Bayes modelling,” was published in Nature Digital Magazine.

To conduct the experiment, participants wore two monitors. One measured physiological stress and relaxation levels through monitoring things like heart rate variability. The second, worn around the neck, measured the sound of the participant’s work environment.

The findings demonstrated that a worker’s physiological wellbeing decreased by 1.9% for every 10 dB increase above 50 decibels in environmental sound level. On the other hand, each 10-decibel increase in office noise, when below 50 dB, was associated with a 5.4% improvement in physiological wellbeing.

This study is part of a wider project run by Sternberg called Wellbuilt for Wellbeing, focusing on the impact of building design on people’s health and wellbeing.

Sternberg suggested that “people are always working in coffee shops – those are not quiet spaces. But the reason you can concentrate there is because the sounds all merge to become background noise. It masks sound that might be distracting. If you hear a pin drop when it’s very, very quiet, it will distract you from what you’re doing. If employee health is a priority,” she concluded, “there’s no reason why these simple interventions can’t be installed in office spaces to mitigate sound distraction.”