### Question
Can you define what octane rating means?


### Answer
**Octane rating** is defined as the following in *15 U.S.C. § 2821*:

> the rating of the antiknock characteristics of a grade or type of automotive fuel as determined by dividing by 2 the sum of the research octane number plus the motor octane number, unless another procedure is prescribed under section 2823(c)(3) of this title, in which case such term means the rating of such characteristics as determined under the procedure so prescribed

#### Citation:
  - *15 U.S.C. § 2821*
  - Heading: **CHAPTER 55-PETROLEUM MARKETING PRACTICES > SUBCHAPTER II-OCTANE DISCLOSURE**

