### Question
What is the definition of replacement ballast?


### Answer
The definition of **replacement ballast** is as follows in *42 U.S.C. § 6291*:

> a ballast that—


(i) is designed for use to replace an existing ballast in a previously installed luminaire

#### Citation:
  - *42 U.S.C. § 6291*
  - Heading: **CHAPTER 77-ENERGY CONSERVATION > SUBCHAPTER III-IMPROVING ENERGY EFFICIENCY > Part A-Energy Conservation Program for Consumer Products Other Than Automobiles**

