Listed below are some notable terms and measurements to keep in mind while shopping for light fixtures.
Lumens (Brightness) – A measurement of how bright a light bulb will shine. The higher the number of lumens, the more light is emitted. For a rough estimate of the lumen required to light a space, the following equation can be used:
(Square Feet of Room) X 20 = Recommended Lumens
Kelvin (Color Temperature) – A measurement of what color is emitted when a light bulb is illuminated. The color temperature spectrum starts at 2000 Kelvin (K), which would be a red tone, and goes up through 6500K, which would be a blue tone. Bright white is used to describe lights with a color temperature between 3100K and 4500K.
Watts (Energy Consumption) – A measurement of electrical power a product requires to operate. Different styles of light bulbs require different amounts of energy to work. Bulbs that have a lower wattage use less electricity.
Color Rendering Index (CRI) – A rating scale that rates how accurately a light source can express true color in comparison to ideal natural lighting. CRI evaluates the color rendition and accuracy of objects under different lights compared to how those objects would look under natural sunlight. Natural sunlight would have a perfect score of 100 CRI. Generally, a CRI of 80 is considered good, while a CRI of 90 or better is thought of as excellent.
Location Ratings – Lighting fixtures are certified by United Laboratories (UL) to be safe for use in the United States. Items are certified for use in one of three environments:
- Dry Location – A location that is rarely or never at risk for moisture.
- Damp Location – A location that is moist or where condensation may build up in and around the fixture.
- Wet Location – A location with direct exposure to water. Water is expected to drip, splash, or flow on or against electrical equipment.