49 CFR § 172.417
FLAMMABLE GAS label
November 18, 2020
(a) Except for size and color, the FLAMMABLE GAS label must be as follows:
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(b) In addition to complying with §172.407, the background color on the FLAMMABLE GAS label must be red.
[Amdt. 172-123, 56 FR 66257, Dec. 20, 1991]