49 CFR § 172.542 - FLAMMABLE placard.
(a) Except for size and color, the FLAMMABLE placard must be as follows:
(c) The word “GASOLINE” may be used in place of the word “FLAMMABLE” on a placard that is displayed on a cargo tank or a portable tank being used to transport gasoline by highway. The word “GASOLINE” must be shown in white.
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