the ballast factor is the ratio of the light output of a fluorescent lamp to the light output of the same lamp operated on a standard (reference) ballast. The ballast factor is multiplied by the rated [..]

A ratio of the actual lumen output for a lamp using ballast to the lumen output for a lamp-ballast system under test conditions established by the American National Standards Institute (ANSI). The higher the ballast factor, generally the more wattage being used by the light fixture.

The measured ability of a particular ballast to produce light from the lamps it powers. Ballast Factor is derived by dividing the lumen output of a particular lamp/ballast combination by the rated lumen output of the same lamp on a reference ballast. A Ballast Factor of 1.0 equals 100% of the lamps rated lumen output.

The ratio of the light output of a fluorescent lamp or lamps operated on a ballast to the light output of the lamp(s) operated on a standard (reference) ballast. Ballast factor depends on both the ballast and the lamp type; a single ballast can have several ballast factors depending on lamp type.