Dotting Your CRI’s and Crossing Your CCT’s

LIGHTING FUNDAMENTAL:
Different tasks require different lighting.
The wrong fixtures will cost you in productivity.

Color Rendering Index (CRI) is an important consideration for task lighting. CRI refers to the ability of a light source to render colors reflected to a standard, such as daylight. Daylight is given a CRI of 100. Higher numbers indicate a light source that will reflect more colors of an object compared to how it would be reflected in daylight. For instance, new T8 lamps offer a CRI of 85 — more colors and better lighting than standard fluorescent and metal halide lamps. 33-60% energy savings coupled with available rebate and grant programs are prompting more and more companies to retrofit with T8 lamps.

Correlated Color Temperature (CCT) is also important in choosing lighting for the correct task. CCT is measured in Kelvin (K). Lower color temperatures (below 3200K) are usually considered warm, while those above 4,000K are considered cool. Daylight is 6500K. 5000K, a popular fluorescent CCT for a cool light, is gaining more prominence in the High Intensity Fluorescent segment for industrial lighting. 5000K is also being preferred in certain office applications. Employees should be considered when choosing to switch, and it is often a good idea to have a test area before switching to a different CCT.

Tags: color rendering index, correlated color termperature, productivity

This entry was posted on Monday, June 15th, 2009 at 9:00 am and is filed under Research and Technology. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.