Lightbulbs

Claimed life

Claimed life is how many years the manufacturer says the bulb will last based on 3 hours of use per day.

Brightness

Brightness indicates the brightness (lumens) of each bulb after 3,000 hours of life testing, as compared with the brightness of a comparable incandescent.

Efficiency

Efficiency is the comparison of the amount of light (lumens) produced by a given amount of electrical energy (watts). The more the lumens per watt the more efficient the bulb.

Light distribution

Measures how well a test bulb duplicates the light distribution of an equivalent incandescent bulb.

Frequent on and off performance

Frequent on and off performance testing reflects the average number of 2-minute on and 2-minute off cycles each bulb survived.

Life testing

Life testing reflects how many 3-hour on and 20-minute off cycles a bulb survives after 3,000 hours of the "on" cycle.

Color accuracy

The averaged measured color rendering of ten bulb samples. Those closer to 100 will better enable colors to appear the same as if viewed under the light of an incandescent bulb.

Warm-up time

Warm-up time is how long the bulb took to reach near full brightness. Bulbs that take 0 to 15 seconds to reach near full brightness scored excellent. Those taking 16 to 31 seconds scored very good, 32 to 46 seconds are good, 47 to 62 seconds are fair, and over 63 seconds scored poor.