ADR Class 4.2 Spontaneously Combustible

Class 4.2 covers pyrophoric substances, which ignite within five minutes of contact with air even in small quantities, and self-heating substances and articles, which heat up in contact with air without an energy supply.

The list below gives every UN number that ADR 2025 Table A (Chapter 3.2) assigns to Class 4.2, with its proper shipping name and packing groups. A UN number with more than one row in Table A (for example one row per packing group or per physical state) is listed once and marked with its row count; its page shows every row. Open a UN number for its classification code, labels, tunnel restriction code, transport category, limited and excepted quantities and the 1.1.3.6 exemption points. The class of a substance is assigned under ADR Part 2 (Chapter 2.2.42); this list helps you find an entry, it does not classify a product.

Entries marked “not subject to ADR” are listed in Table A but carried outside ADR under the conditions their special provision sets; entries marked “carriage prohibited” may not be carried at all.