Which document stipulates the "Four Necessary Inspections" for the storage, loading and unloading of hazardous chemicals?

It is necessary to check whether the road transport license of the vehicle, the qualification certificates of drivers, escorts and loading and unloading operators are compatible with the loaded goods or dangerous goods;

Need to check whether the pressure vessel is delivered or filled with dangerous goods within the inspection validity period;

Before delivery or filling of dangerous goods, it is necessary to check whether the vehicle is hung with signs that meet the requirements of the national standard "Road Dangerous Goods Transport Vehicle Signs";

Enterprises that sell highly toxic chemicals and dangerous chemicals that are easy to produce explosives must check the corresponding purchase licenses or supporting documents when delivering or filling.