spontaneously combustible placard
Class 4.2 is for materials that self-heat and catch fire on contact with air without any flame — white phosphorus above all, plus certain metal catalysts and oil-soaked rags. The diamond with a white upper half, a red lower half and the flame symbol warns that opening or tearing the package can start a fire on its own.
Where is it used and when is it required?
Applied to drums, sealed packages and containers, on the doors of specially ventilated chemical stores, in warehouses in industrial cities, on trucks carrying dangerous goods, and in laboratories that keep phosphorus and catalysts under a protective liquid.
Regulation notes
GHS, the Globally Harmonized System of Classification and Labelling of Chemicals, is the classification system adopted across the Gulf, and the placard's colours, symbol and class number all derive from it. Placarding stores, containers and vehicles is the expected practice in Saudi and UAE industrial zones whenever dangerous goods are stored or moved.
- The usual placard size on trucks and containers is 250 × 250 mm; a 100 × 100 mm label is enough on a drum or a single package.
- Use a weatherproof, UV-resistant material — the contrast between the white and red halves is what tells this placard apart from class 3.
- Keep the class number "4.2" at the bottom corner clear and unobstructed by shipping labels or sealing tape.
Size guide
Choose the size from the maximum distance the sign must be read from (ISO 3864-1 guidance).
Print tip: use card stock or mount on foam board/acrylic, and print the PDF at 100% (not “fit to page”).
This sign is also known as: spontaneously combustible placard، class 4.2 hazmat placard pdf، self-heating substance sign printable، dangerous goods class 4.2 label. Informational sign not governed by a mandatory standard; designed in one consistent style for everyday use.
Included in packs
- Hazmat kit — $15
