49 C.F.R. § 451.23 – Plate specifications.

(a) The safety approval plate must be of the size and in the format specified in the appendix to Annex I to the convention.
(b) The safety approval plate must be:
1. (1) Designed to withstand and remain legible after a 15 minute exposure to a medium intensity fire producing a temperature of 1,000 °F (540 °C), when mounted on the specified material of construction of the container.
2. (2) Designed to resist the corrosive effects of its environment, both at sea and ashore, so as to remain legible for the working life of the container.
3. (3) Designed to have a legible life expectancy equal to or greater than the life expectancy of the container to which the plate is affixed.