ADR hazard number X668
Hazard identification number X668 on the orange plate: highly toxic, corrosive substance that reacts dangerously with water.
Printed in the upper half of the orange-coloured plate above the UN number, X668 identifies a highly toxic, corrosive substance that reacts dangerously with water. A repeated figure means that hazard is intensified. The leading X warns that the substance reacts dangerously with water, so water may be applied only with expert approval.
| X | prefix X: the substance reacts dangerously with water; water may be used on it only with the approval of experts |
|---|---|
| 6 | toxic, or a risk of infection |
| 6 | repeated 6: doubling a figure means that hazard (toxic) is intensified |
| 8 | corrosive |
Note. 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 3 Table A entries
Source: ADR 2025 (ECE/TRANS/352), Volume II, section 5.3.2.3.2, X668, page 268.
Paraphrase in FreightUtils' own words, not the official text. Not yet reviewed.
ADR 2027 amendments (accepted, applying from 1 January 2027) are not yet reflected on this page.