Light and Sound in the Healing Environment

April 29, 2026

Patient and Staff Wellbeing

Healthcare environments are increasingly being understood as systems shaped not just by clinical care, but by the sensory conditions that surround patients and staff. Among these, light and sound stand out as two of the most influential environmental factors, as they directly affect physiological regulation, psychological wellbeing, and recovery outcomes.

Lighting strategies that align with circadian rhythms and support natural biological cycles have been shown to improve sleep quality, reduce stress, and even shorten hospital stays, while poorly controlled lighting can disrupt recovery and increase fatigue. Similarly, excessive noise has been consistently linked to sleep disruption, elevated stress responses, and delayed healing. Taken together, these conditions underscore how deeply the built environment is intertwined with patient experience, shaping how spaces are organized, detailed, and ultimately inhabited.

The Role of Lighting in Healing Environments

The role of lighting in healing environments may be one of the most important focuses for patient and staff wellbeing. Studies show that exposure to daylight improves mood and pain perception, with some facilities reporting reduced depression and pain medication distribution after introducing more natural light. To go even further, one study found that ICU patients parallel to large windows left the ICU around 17 hours sooner on average than patients in beds near a door or away from windows. 1

The effects of lighting on patient wellbeing mostly stem from circadian stimulation. Different levels of illumination give the brain cues on when to produce melatonin for sleep, and when to stop melatonin production for an energy boost. A new approach to healthcare lighting2 is driven via light therapy techniques. 24-hour lighting schemes focus on stimulating the eye with a circadian-effective light source for at least two hours a day. During evening hours, lighting is focused on lower illumination in order to complement the brain’s circadian rhythm. Suggested benefits of following this lighting technique includes reduction in depression, agitation, and a significant decrease in fall-risk.3 4

Other facets to consider when selecting healthcare lighting is color temperature and lighting selection. Studies show that cooler temperatures (~4000-5000K) during the daytime may boost alertness, while warmer temperatures (~2700-3000K) in the evening prepare the body for rest.5 This study explored the effect of time-sensored task-based lighting during evenings and found that it reduces patient disruption and anxiety levels when opposed to overhead lighting.

Sound in Healing Environments

According to AAMC, “The World Health Organization, International Noise Council, and Environmental Protection Agency have proposed noise limits for hospitals ranging from a 35-45 A-weighted decibel [dB(A)] level during the day to a 20-35 dB(A) level at night. Despite this recommendation, numerous studies have found that noise levels throughout hospitals at all times of day significantly exceeded this limit. For example, one study from Johns Hopkins Hospital found a daily average sound level of 50-60 dB(A) (analogous to a crying baby or vacuum cleaner), as well as a trend of increasing noise levels over the past 45 years.”6 Noise during the evenings disrupts sleep and elevates stress. One ICU study found that noise accounts for ~75% of patient sleep disturbances.7 This study demonstrates that a majority of ICUs have sound levels above the recommended level, with the average exceeding 51 dBA at 4 AM (roughly the sound of a refrigerator hum). Poor sleep leads to delirium in 30-75% of ICU patients, and even short noise spikes raise blood pressure and cortisol.

Designing auditory solutions in the healing environment requires a multi-faceted approach. Acoustic treatment, space layout, and reduction in noise sources yields a larger reward than a single-channel approach. Acoustic treatment (soft ceiling tiles, wall panels, door seals, etc.) can cut reverberation time and lower noise transmission. A 2023 hospital ward study showed that installing absorptive ceilings and new doors cut reverberation by 30-50% and reduced room noise by 5-11 dB.8 Patients and staff reported less noise disruption, with patients noting better sleep, and staff noting higher efficiency and lower conversation volumes.

When designing the space, strategic layout can also isolate noise. Locating nurses’ stations and utility rooms away or separate from patient rooms prevents reverberation across spaces. Designers can also separate waiting rooms by using sound-lock lobbies or buffering hallways with storage spaces.

In addition to layout and noise absorption, technology and work culture contribute to the sound levels in healthcare spaces. Technology solutions can be used to separate patients from sound sources. Patients can be provided headphones, ceilings can have white-noise systems to mask sudden noises, intercom systems can be less disruptive by using visual-based systems first. Designers should work with their client to reduce the amount of sound pollution in order to increase patient satisfaction and reduce anxiety. In addition to tech, work culture and workflow also contribute to sound levels. Any rogue alarms/systems must be dealt with quickly, and reduced intercom use are two work-focused ways to make the environment quieter for patient and staff experience. Layout, noise absorption, technology, and work culture all individually reduce noise pollution in healing environments, but combined approaches yield the biggest gains.

References

  1. Park, M. Y., Chai, C.-G., Lee, H.-K., Moon, H., & Noh, J. S. (2018). The effects of natural daylight on length of hospital stay. Environmental Health Insights, 12. https://doi.org/10.1177/1178630218812817
  2. Hanford, N., & Figueiro, M. (2013). Light therapy and Alzheimer’s disease and related dementia: past, present, and future. Journal of Alzheimer’s disease : JAD, 33(4), 913–922. https://doi.org/10.3233/JAD-2012-121645
  3. Okinami, T., Suzuki, T., Nishikawa, N., & Negoro, H. (2025). Circadian Lighting Was Associated with a Reduction in the Number of Hospitalized Patients Experiencing Falls: A Retrospective Observational Study. Healthcare (Basel, Switzerland), 13(14), 1692. https://doi.org/10.3390/healthcare13141692
  4. Grant, L. K., St. Hilaire, M. A., Heller, J. P., Heller, R. A., Lockley, S. W., & Rahman, S. A. (2022). Impact of upgraded lighting on falls in care home residents. Journal of the American Medical Directors Association, 23(10), 1698–1704.e2. https://doi.org/10.1016/j.jamda.2022.06.013
  5. Albala, L., Bober, T., Hale, G., Warfield, B., Collins, M. L., Merritt, Z., Steimetz, E., Nadler, S., Lev, Y., & Hanifin, J. (2019). Effect on nurse and patient experience: overnight use of blue-depleted illumination. BMJ open quality, 8(3), e000692. https://doi.org/10.1136/bmjoq-2019-000692
  6. Jawadi, Z., & Chern, A. (2023, August 10). Hospitals are noisy. They don’t have to be. Association of American Medical Colleges. https://www.aamc.org/news/hospitals-are-noisy-they-dont-have-to-be
  7. Darbyshire, J. L., & Young, J. D. (2013). An investigation of sound levels on intensive care units with reference to the WHO guidelines. Critical care (London, England), 17(5), R187. https://doi.org/10.1186/cc12870
  8. Deng, Z., Xie, H., & Kang, J. (2023). The effectiveness of acoustic treatments in general hospital wards in China. Building and Environment, 244, 110728. https://doi.org/10.1016/j.buildenv.2023.110728