Light is light, right? Not exactly. The light that comes from the overhead fluorescents at your office is nothing like the light that pours from your favorite chandelier at home or that of the bedside lamp that lets you read your favorite novel to help you fall asleep.
That's because different light sources produce light with different color temperatures. In the early days of energy conservation, everyone recommended replacing incandescent bulbs with fluorescent bulbs because the latter consumed less electricity. But few people liked the tradeoff because of the quality of light the energy-efficient bulbs produced.
That didn't stop Congress from mandating the phase-out of incandescent bulbs, but it did prompt the lighting industry to come up with better alternatives. As you think about which type of lighting to use in your home, you should consider how you can use color temperature to optimize your environment. Here's everything you need to know.
How color temperature works
To understand why color temperature is important, you must first to understand what it is. This can be a tricky concept, so let's break it down to basics.
Imagine a hypothetical black, metal object — say, the filament of an incandescent light bulb. Now begin heating this filament with hypothetical fire. As the filament heats up, it will begin to glow, first red, then yellow, then white, and then various shades of blue as the flame gets hotter and hotter.
Certain temperatures of this flame, measured on the Kelvin temperature scale, correspond to various wavelengths of light from the filament. The bottom end (around 1800 Kelvin, or 1800K) corresponds to the intensely red-orange light from a match or candle. At the high end (15000K and up), the readings correspond to the light observed looking up at a clear, blue sky.
You're probably familiar with terms like "cool white" and "warm white" lighting, like those you've seen on a standard incandescent or fluorescent light bulb. If you read the fine print on the back of a light-bulb package, you might even find an estimated color temperature denoted in degrees Kelvin.
Most commercial lighting falls between about 2000K and 6000K, but two color temperature levels dominate. Around 2700K is typically denoted as "warm white" or "soft white." These bulbs are designed to approximate the typical incandescent bulb, offering an orange-tinted, cozy, "warm" light just like at grandma's house. Warm light is considered a comfortable, homey light most suitable for use in the home.
At about 3500K we enter the realm of "cool white" or "bright white." Lamps at this color temperature take on a more neutral color and may appear to have a slight blue cast. Standard fluorescent lighting is typically produced at this color temperature, and it's what you'll find in most business environments, as light at this wavelength is considered ideal for reading and other detail-oriented task work.
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