21.110—Gasoline, unleaded.
         Conforms to specifications as established by the American Society for Testing and Materials (ASTM) in the 1980 Annual Book of ASTM Standards,  Part 23, page 229, Standard No. D 439-79. Any of the “seasonal and geographical” volatility classes for unleaded gasoline are considered suitable  as a denaturant. (For incorporation by reference, see  § 21.6(b).)