Hazardous substances are an integral part of life, and people are not even aware of it. Tankers and trains pass by all of us every day, and airplanes fly in the sky in such a large number that it would be impossible to count them all. During the summer holidays, there are always ships nearby that also transport dangerous cargo. If attention were started to be paid to them, it would be seen how many of them actually transport some kind of dangerous substance. The most common dangerous substances that are transferred are liquids and gases. The most common flammable liquids that everyone uses without even thinking about it are gasoline and diesel fuels. They are used not only in cars and other means of transport, but also in large production plants, for heating, but also for cleaning because they are good degreasers. Flammable liquids are listed as just one example of how dangerous substances are taken lightly, and the potential dangers they can cause are not even thought about. This is precisely why it is important to know how to properly handle any dangerous substance, especially with substances that are classified as highly flammable liquids, and this especially applies to all workers who participate in their storage and transport. It is also important to know how to act in case of any incident and to properly protect yourself from them.