Dangerous When Wet Hazard Sign - Class 4.2 Flammable Solid Warning #1384858 (License: Personal Use)

This is a standardized UN hazard warning label (Class 4.2) used globally for substances that react dangerously with water-producing flammable gases, heat, or spontaneous ignition. The bright blue background, black flame pictogram, and bold uppercase text ensure high visibility and immediate recognition in industrial, transportation, and laboratory settings. The numeral “4” at the bottom denotes Division 4.2 within Class 4 (Flammable Solids).

Used on packaging, shipping containers, safety data sheets, and facility signage to warn handlers about water-reactive hazards; aligns with OSHA, DOT, and GHS compliance for chemical safety communication.