Welcome to David City
Welcome to David City
To enhance the vibrant community of David City by providing a tremendous quality of life defined by outstanding educational and employment opportunities for all citizens through provisions of quality, cost effective governmental services that include infrastructure, utilities, and affordable housing.
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As a child, I remember doing homework at the kitchen table around dusk one evening when my father walked in and said, “How can you see? Turn the light on!” I could not believe this came from the same guy who was always telling me, “Turn the lights off when you leave a room!” I could see just fine!
Several decades later, I have aged past that point in my father’s lifetime and finally realize why he would question my ability to see. He could not. And now, I cannot either.
As everyone ages, a number of things occur in our eyes that degrade vision. From the day we are born, the lens of our eyes yellow with age. Usually after age 40, hardening of the lens capsule and often, atrophy of the ciliary muscles that focus the lens create a condition known as “presbyopia” which is the loss of being able to focus on things close up.
Shape and clarity changes in the cornea (clear outer covering of the eye) cause light to refract which decreases the amount reaching the retina. Our iris’ ability to regulate pupil size decreases and limits the amount of light entering the eye as well as the ability to quickly adjust sight to different lighting levels.
As if these symptoms of aging are not enough, our lenses cloud (cataracts) and the vitreous fluid inside the eye takes away our abilities to discern contrast and colors. To top it off, increased scattering of light inside the eye makes us more susceptible to glare.
What is an old set of eyes supposed to do? Best answer: Accommodate for these natural changes. Start by providing more light. The Lighting Research Center at Rensselaer Polytechnic Institute estimates that for the same light level, a typical 60-year old receives about one-third the retinal illuminance of a 20-year old. Consider some remodeling using light-colored surfaces (ceiling, walls, floor, furniture, etc.) in order to maximize the amount of light in a room.
Improve the uniformity of light distribution to reduce shadows. Try to maintain uniform lighting within a room, as well as from one room to another. Since older eyes take longer to adjust to changes in light levels, this will increase safety while moving about.
Select glare-free light fixtures as glare reduces the ability to see subtle details at lower light levels. Avoid fixtures with bare or exposed light bulbs or tubes as these notoriously produce glare.
At night, use several in-wall and/or plug-in night lights in bedrooms, bathrooms and kitchens to safely navigate through your home. Look for night lights that provide an amber-reddish light rather than a bluish-white light to avoid interrupting natural human circadian rhythms.
Finally, start by looking at LED (light-emitting diode) bulbs, tubes and fixtures for providing solutions to the abovementioned concerns. Why? Because LEDs tend to be more directional in dispersing light so that it can be focused on what is being lit rather than scattering light around as other lighting technologies do. LEDs are often twice as energy efficient as fluorescent and four times more efficient than incandescent lights. Plus, LEDs come in options varying from very
cool white to warm white with a reddish glow to correlate with time-of-day lighting recommendations. LEDs also tend to have a much longer-rated life than other lighting technologies which means a replacement may not be needed in the future.
Your local electric utility and Nebraska Public Power District want to help customers illuminate the dark corners of their world and make the most of every dollar spent on energy. They may also offer EnergyWiseSM energy efficiency financial incentives to offset the cost of installing LED technology. Contact your local utility or visit www.nppd.com to find out more.