Personnel injured by use of hot air guns
This is an synopsis of several similar incidents
Hot air guns are often used as a easily available heat source, indeed they can be invaluable in the laboratory to prevent solidification on distillation of low melting solids. However several incidents have been seen where they have been used to heat flasks of flammable liquids, in these cases, the flask has cracked and the spilled liquid has ignited with the heat of the gun. The resulting fire can lead to disastrous consequences, and at least one person has been know to be killed.
Hot air guns are very hot, some will give temperatures in excess of 400°C, and 600°C is not uncommon. With these sort of temperatures, it is very easy to stress the glass, if the gun is not moved about enough, and the temperature of the gun is often past the autoignition point of many solvents. The gun should be treated as one would treat a bunson burner, and thus not used to apply heat to heat a flammable solvent, they are ideal for warming glassware, but very inefficient in heating quantities of liquid - an indirect heating bath is by far the safer option.