All combustible gases or vapors, when mixed within definite amounts, are explosive. The violence of the explosion will be in proportion to the volumes of the gas and the condition of confinement.

When gasoline or other volatile fuel is vaporized in a closed room, there is danger of an explosion, should the mixture of the vapor and air reach explosive proportions. It is dangerous to enter a room with a lighted match or open-flame lamp, where gaseous odor is markedly noticeable. In case of danger of this kind the windows and doors should be immediately opened to produce the most rapid ventilation.

In the act of igniting the flame in a gas or vapor stove, the lighter should be made ready before the gas is turned on. Explosions in gas and vapor stoves are usually due to carelessness in igniting the fuel. It should be kept constantly in mind that, if a combustible gas is allowed to escape and mix with air in any space and then ignited, an explosion of more or less violence is sure to occur.

Gasoline and kerosene are lighter than water and will float on its surface. The flames from these oils are aggravated when water is used in attempting to extinguish them. The burning oil floating on the surface of the water increases the burning surface.

Burning oil must be either removed to a place where danger will not result or the flames must be smothered. In case of a small blaze, the fire may be extinguished with a cloth, preferably of wool, or if circumstances will permit, with ashes sand or earth.

Alcohol dissolves in water and may therefore, be diluted to a point where it will no longer burn.