By Despina Tselegkaridou
Senior Lighting Consultant at CBRE
For a better, healthier and more sustainable world, it is important to understand that the type, pattern and quality of lighting in buildings is key.
Beyond the elementary safety issue of providing enough light for people to see and complete tasks, it is imperative to delve further. Increasingly considered questions are:
- Can LEDs keep you awake at night and damage your brain?
- Can special lighting increase productivity?
- Can bad lighting be a cause of specific types of cancer?
A piece of research funded by BRE Trust, the largest UK charity dedicated to research and education in the built environment, with researchers from universities in Istanbul and Eindhoven have summarised the factors – such as the effects on health and mood – that building occupiers, owners and designers should be aware of:
- Adequate lighting and lighting controls. This includes the provision of emergency lighting to enable people to work and move around a building, or an external site, safely.
- Poor lighting. Particularly lighting that causes glare, can give visual discomfort which may result in sore eyes, headaches, and aches or pains associated with poor body posture. These issues can be avoided by careful lighting design that meets standard codes of recommendation.
- Fluorescent lighting with magnetic ballasts and some Light Emitting Diodes (LEDs) can exhibit mains flicker, which can cause headaches, eyestrain or epileptic seizures while exacerbating the symptoms of autism and agoraphobia. Switching to high frequency fluorescent lighting, or different types of LED driver, averts such problems.
- Synchronisation of the body clock. Frequent changes to the body clock, e.g. variable shift schedules or time zone changes are associated with a range of health issues including some cancers. Sources rich in blue light, such as daylight, LEDs and some fluorescent lamps, tend to alter the body clock the most.
- Seasonal Affective Disorder (SAD). This is an illness which causes depression in winter at high latitudes when there is less daylight. Exposure to bright light can alleviate the symptoms of SAD.
- Very bright light can cause eye damage. Most conventional lighting, including fluorescent lighting, is not bright enough to cause eye damage. However, some very bright LEDs, particularly blue LEDs, may cause retinal damage if viewed directly. Such lighting should be screened from direct view while in use.
- UV radiation can cause skin cancer. For example an unprotected lamp, particularly a Compact Fluorescent Lamp (CFL) with a faulty phosphor coating, may emit some UV radiation. To be on the safe side, desk lamps which might be close to a user for a long period should either have a protective transparent cover to the lamp, or use LED lamps which emit little or no UV radiation.
- Improve daylight provision. Providing daylight in buildings is often a convenient way to regulate circadian rhythms, resulting in improved health and mood.
- Mercury rising. Fluorescent lamps and other gas discharge lamps contain mercury. Intact lamps do not release mercury but health risks to consumers can arise from accidental lamp breakage. It is important that broken lamps are disposed of safely, and lamps are processed at the end of life to recover the mercury. LED lamps currently available on the market should not contain chemicals above human toxicity levels.
Given the above advice, it's prudent for occupiers, owners and developers of buildings to ensure correct attention is paid to the lighting to ensure effective wellbeing for all.