It is the sign of toxic gas, mainly the sign of dangerous chemicals, explosive substances or articles, in which black or white patterns and red icons represent flammable gas symbols.

Black or white pattern, if the background color is green, it means flammable gas and non-toxic gas symbol.

Skull stands for danger, and commonly used hazardous chemicals are marked by Classification and Marking of Commonly Used Hazardous Chemicals (GB 13690-92). Generally, the background color is white, with black skull and Crossbones shape.

Safety signs are signs that warn workers of the dangerous situation in the workplace or the surrounding environment and guide people to take reasonable actions. Safety signs can remind staff to prevent danger, thus avoiding accidents; When danger occurs, it can instruct people to flee as soon as possible, or instruct people to take correct, effective and effective measures to contain the harm.