Patient rooms. Where light becomes part of therapy
Patient rooms are spaces where individuals often spend many hours each day. This is where light can have the strongest influence on circadian rhythms, sleep quality, and recovery processes.
Lighting design in patient rooms should not focus solely on providing an adequate number of lux. More importantly, it should create an environment that enables a natural distinction between day and night.
In practice, this means incorporating several complementary layers of lighting:
- general lighting for everyday activities,
- biologically effective lighting that supports daytime alertness,
- individual reading lights,
- night lighting that allows safe movement without disturbing patients,
- care-related lighting scenes for medical staff.
Increasingly, healthcare facilities are also introducing patient-controlled lighting. Research on healing environments indicates that a sense of control over one's surroundings can reduce stress and improve the perceived quality of hospitalization.
Intensive care units. One of the greatest design challenges
Intensive Care Units (ICUs) are among the most demanding environments for lighting design.
Patients may remain there for days or weeks with limited activity, often under sedation and with little or no access to natural daylight. At the same time, healthcare professionals perform highly precise procedures around the clock and must remain constantly alert.
Recent studies suggest that circadian rhythm disruption is one of the factors associated with an increased risk of ICU delirium, which can lead to longer hospital stays and poorer outcomes.
For this reason, dynamic lighting systems are increasingly recommended to:
- clearly mark the beginning of the day through increased light exposure,
- gradually reduce light intensity in the evening,
- maintain very low levels of biologically active light during nighttime hours,
- provide staff with adequate visibility for patient monitoring.
Proper lighting scene management is critical. Clinical lighting scenes should only be activated when medical procedures are being performed, while the default environment should support patient recovery and regeneration.
Geriatrics. Light as a tool to prevent disorientation
Older adults represent a particularly important group of users.
Aging reduces the amount of light reaching the retina, decreases contrast perception, and weakens biological responses to light stimuli. At the same time, geriatric patients are more likely to experience sleep disturbances, disorientation, and neurodegenerative conditions.
A well-designed lighting environment can help mitigate some of these issues.
In practice, this involves:
- increasing access to daylight,
- improving illumination of vertical surfaces,
- reducing deep shadows,
- eliminating glare,
- implementing clearly differentiated daytime and nighttime lighting scenes.
Research led by Professor Mariana Figueiro has shown that appropriate daytime light exposure may improve sleep quality and reduce symptoms of disorientation in people living with Alzheimer's disease and other forms of dementia.
Psychiatry and mental health
The importance of light is particularly evident in psychiatric settings.
Circadian rhythm disorders are common symptoms of depression, bipolar disorder, and anxiety disorders. A growing body of research indicates that a properly designed lighting environment can support sleep-wake cycle stabilization and improve patients' overall well-being.
This does not mean that light replaces medication or psychotherapy. However, it can serve as an important component of environmental therapy, alongside access to nature, good acoustics, and ergonomic design.
In practice, special attention should be given to creating calm, glare-free lighting scenes with balanced luminance distribution.
Healthcare professionals. The often-overlooked beneficiaries of good lighting
When designing hospital lighting, it is easy to focus exclusively on patient needs. However, healthcare professionals are equally important users of these environments.
Doctors, nurses, paramedics, and technicians often spend long hours working in shift-based schedules. Fatigue caused by circadian rhythm disruption affects not only their health but also patient safety.
Research in workplace ergonomics suggests that appropriate lighting conditions can improve:
- concentration,
- decision-making speed,
- procedural accuracy,
- comfort during extended shifts.
Biologically effective lighting design should not require choosing between patient and staff needs. The goal is to create a flexible environment that allows lighting scenes to adapt to different activities throughout the day.
Daylight. The first and most important designer
Despite the rapid advancement of LED technology, natural daylight remains the most effective factor for synchronizing human circadian rhythms.
For this reason, biologically effective lighting design should begin not with fixture selection but with an analysis of the building's architecture.
Key considerations include:
- building orientation,
- window size and placement,
- room depth,
- daylight access at staff workstations,
- visibility of changes in the outdoor environment.
Only where daylight proves insufficient should properly designed artificial lighting take over its role.
This approach aligns with both Human Centric Lighting principles and sustainable design strategies, including the WELL Building Standard.
The most common design mistakes
The growing popularity of Human Centric Lighting has led to the term being used as a marketing label without meaningful implementation.
Several recurring mistakes can be identified:
- equating HCL solely with tunable white technology,
- designing exclusively according to illuminance values on working planes,
- ignoring eye-level exposure and luminance distribution,
- failing to coordinate architectural, electrical, interior, and clinical design processes.
The best outcomes are achieved when lighting design is integrated with architectural planning and hospital workflow development from the earliest project stages.
Conclusion
Biologically effective lighting in hospitals is about far more than achieving required illuminance levels. Modern lighting design is based on an understanding of how light affects circadian rhythms, sleep quality, well-being, and staff performance. The primary objective is to create an environment that reinforces the natural distinction between day and night, reduces stress, and improves patient comfort throughout the healing process.
The most effective results come from combining daylight, intelligent lighting controls, and the principles of Human Centric Lighting and Evidence-Based Design. This approach helps create healthcare environments that not only meet technical requirements but also actively support health, recovery, and well-being.