What does color temperature mean in lighting?
Color temperature is measured in Kelvin (K) and determines the color of light emitted. The higher the Kelvin, the whiter the color temperature. This is often expressed as the warmth (reddish) or coolness (bluish) of the white light. There are three primary types of color temperatures; soft white, bright or cool white and daylight. Soft white is typically between 2700K and 3000K, bright or cool white are between 3500K and 4100K and daylight is between 5000K and 6500K.
The horizon on a sunny day is approximately 5000K while an overcast day can be a cool 6500K. Indoor incandescent lights are typically warm and approximately 2700K. Metal halide and high-pressure sodium bulbs have a fixed color temperature whereas LEDs can be manufactured with different color temperatures. LEDs are typically 3000K, 4000K or 5000K.
3000K – Friendly and inviting spaces such as restaurants and hotels
4000K – Neat, clean and efficient spaces including retail stores, mass merchants, kitchens and garages
5000K – Bright, alert, exacting coloration often found in warehouses, healthcare and sports stadiums