ADR hazard number X423

HIN X423 (orange plate): solid, flammable solid or self-heating solid that reacts dangerously with water, giving off flammable gas.

Printed in the upper half of the orange-coloured plate above the UN number, X423 identifies a solid, flammable solid or self-heating solid that reacts dangerously with water, giving off flammable gas. This is one of the figure combinations that 5.3.2.3.1 gives a special meaning, read as a whole rather than figure by figure. The leading X warns that the substance reacts dangerously with water, so water may be applied only with expert approval.

Note. 5.3.2.3.1 lists 423 among the combinations with a special meaning, so read it as a whole from the 5.3.2.3.2 list; the per-figure reading in digits[] does not fully apply. In the 5.3.2.3.2 list this entry carries footnote 1: water is not to be used except with the approval of experts. Number and meaning pairing checked against a second text extraction of the list.

Refers to: 5.3.2.3.1; 5.3.2.2.3; Table A column (20).

Carried by 14 Table A entries

UN 1402 · UN 1407 · UN 1415 · UN 1423 · UN 1428 · UN 2257 · UN 2813 · UN 3395 · UN 3396 · UN 3397 · UN 3401 · UN 3402 · UN 3403 · UN 3404