49 CFR § 172.530
OXYGEN placard
November 18, 2020
(a) Except for size and color, the OXYGEN placard must be as follows:
(b) In addition to complying with §172.519 of this subpart, the background color on the OXYGEN placard must be yellow. The symbol, text, class number and inner border must be black.
[Amdt. 172-123, 56 FR 66262, Dec. 20, 1991]