49 CFR § 172.554 - POISON placard.
(a) Except for size and color, the POISON placard must be as follows:
(b) In addition to complying with § 172.519, the background on the POISON placard must be white. The symbol, text, class number and inner border must be black. The word “TOXIC” may be used in lieu of the word “POISON”.
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