Color rendering index (CRI) is a light’s ability to produce all the colors of the spectrum. This quantitative measure is used for lighting fixtures to determine how closely the light can produce the colors and a bright white light.
T8 lamps, the efficient counterpart to the obsolete T12 lights, have four types of CRI: 835, 841, 850, and 865. You can see the differences in the photo on the right.
The lamps with a higher CRI provide a bright white light, and the ones with a lower CRI do not. Because of the varying light differences, all four lamps are ideal for a variety of applications. And with their 5-year warranty, require very little maintenance.
For example, the CRI 865 lamp would be great for offices to increase productivity. The CRI 835 lamp shines well for bathrooms, or any area that requires a soft glow.
Do your lighting fixtures look like these? Consider more efficient lighting with T8 lamps and ballasts.