Lightning and Eye

Lighting in our homes can have a profound effect on the quality of our life. Proper illumination may compensate for many age-related changes in the visual system. A sixty-year-old needs ten times as much light as a normal twenty-year-old to perform the same seeing task with equal speed and accuracy.

Lighting makes a significant contribution to our physical and psychological functioning. Better lighting can help increase personal independence, promote health and well-being, and prevent injuries.

In general, we should attempt to provide higher levels of illumination throughout the entire house. As we age, patterns of activity change. The visual tasks associated with a normal life (i.e. matching clothing colors, grooming and getting up in the middle of the night to read or use the bathroom) all need to be considered in the lighting design. Kitchens and bathrooms particularly need better lighting because work there is detailed.

Reading small print on a medicine bottle in the middle of the night is standard and not being able to do this is potentially hazardous. Accent lighting adds visual interest and becomes important for orientation and safety. As we age, it becomes more critical to clearly define hallways, stairs, and potential changes in surfaces or levels. Proper lighting can do this effectively.

Lighting design must balance between creating visual interest and visual disruption. This is particularly critical with older eyes that find blurred vision or changes in contrast unsettling. Scallop lighting effects on hallway walls or alternating high and low illumination levels within a space create a visual distraction. Shiny floors provide another source of glare and the resulting light patterns can be disorienting. It is also helpful to visually define where the wall meets the floor and avoid shadows which effect detail perception a higher ambient light level is helpful in creating pleasantly lit areas.

Outside light can be up to 1000 times brighter than the interior. Excessive differences in lighting levels should be avoided in transition areas between driveways, garages, entries, lobbies and corridors. Doors should be clearly delineated and pathways well illuminated. Older eyes adapt more slowly to changes in the light levels between rooms so having a more even distribution of light makes navigation easier.

As eyes age, they lose their ability to distinguish color, particularly in the short wave lengths (blue,violet). Living with effective light is a combination of designing good lighting and using it correctly. The primary consideration is the location and selection of lighting fixtures and controls. Fixtures should be carefully selected for their light quality. Bare bulbs fixtures should be avoided because they cause glare spots to which the older eye is painfully sensitive. Task light should be selected to provide adequate light for the task and to be adjustable in location, direction and intensity for individual needs. In both cases, high illumination per fixture does not add to the quality of light, in fact often the opposite is the rule. More fixtures with lower wattage create a more comfortable environment.

Controls are essential for the lighting systems to perform adequately. Controls for turning on and off lighting can include basic switches, dimmers, automatic sensor switches and scene controls. Although we want to consciously control our environment, we must consider whether it is appropriate to hunt for a light switch where issues of safety are involved. Motion sensors can turn lights on as we pass through an area.

This is particularly effective in hallways, stairs or in areas where hazards must be avoided. Timing lights to switch on or off can be an effective way to insure adequate ambient lighting as the daylight changes. A group of light switches may be controlled together providing scenes that balance light from many sources by simply pushing one switch. Switches can be located to control groups of lights for convenience, effect and safety. A single switch located at your bed can turn on a night light pathway to the bathroom or kitchen. Lighting can be incorporated into the security system so adequate light is turned on to safely mark an exit path in case of emergency.

Some general rules to consider

• As we age, quality lighting becomes more important than ever
• Since we spend more time in our home, lighting through the day should be a normal consideration
• Ambient lighting should be available at sufficient levels to positively effect us physically and psychologically
• General lighting levels should be significantly higher than is normal practice
• Task lighting must be carefully arranged to illuminate the task while avoiding glare
• Accent lighting should be used to provide interest and information and avoid visual noise
• Daylighting is the most significant element in lighting a home. It must be filtered to prevent glare and sharp contrasts from area to area.
• Lighting should have controls that are is easy to use.