Light is essential for orientation to the environment. Most everyday activities are impossible without adequate light. For detainees, having access to natural light helps create a connection to the outside world. Light also helps people orient themselves relative to other objects, and therefore has a direct impact on spatial awareness. Darkness increases a sense of enclosure and can cause fear and loss of a sense of self. Periods of darkness are essential, however, to induce rest and sleep. The presence of light during the day, and darkness at night, is fundamental to how we measure the passing of time.
Light, sunlight in particular, is essential for several physiological processes and for mental wellbeing. Both overexposure and underexposure to light (including sunlight) and darkness can have serious impacts on health and wellbeing. In the short-term this can cause disorientation and disturbed sleep patterns. Longer-term, those unable to absorb enough sunlight through their skin may suffer from Vitamin D deficiency and be more at risk from schizophrenia, cardiovascular disease, and damage to the immune system. Many hormones and neurotransmitters are affected by light, including serotonin, low levels of which can cause depression and anxiety.
Some people may be especially vulnerable to deprivation of light, particularly natural light, including people with pre-existing mental health or neurodivergent conditions. Light deprivation puts children at risk from the impact on growth and development. Risks from underexposure to natural light may also be compounded in certain geographical areas.
Deprivation of light can be an indicator of other issues, including lack of ability to exercise. Deprivation of sunlight may co-occur with poor ventilation through lack of windows. The mere presence of windows does not solve the problem if they are dirty, obscured, or inaccessible.
Key Considerations for Detention Monitors
Inside sleeping accommodation, is there enough light (natural in daytime, artificial in evenings) for you to read?
In longer-term detention, e.g., prison, can you clearly see the view outside – not just the sky – through windows (in-cell and in communal areas)? Barriers might be internal (e.g. fixed furniture) or the window itself (e.g. tinted or dirty windows).
In rooms where detainees sleep, can lights be turned on and off in the room, rather than remotely? Where a level of constant lighting is needed for safeguarding, is it bright enough to disturb sleep? Is it different to daytime lighting levels? Do staff use this light only following an individualised risk assessment?
Are all detainees able to spend at least one hour a day outdoors, if they want to?
Is the outdoor space open or covered?
Can detainees access SPF products to protect against harmful effects from sunlight?