A fog machine produces a dense vapor that resembles fog or smoke. It vaporizes a fluid known as fog juice and pumps the vapor into the open air. When this vapor contacts moisture in the air, it condenses to form a thick fog. Fog machines are most commonly used in professional entertainment but they’re also available to individuals. Fog juice is generally too dangerous to mix at home but you can safely make a specific type of fog juice that uses glycerine and water.
Use distilled water. All types of fog juice must use distilled water because ordinary water will clog the fog machine with mineral deposits. You can obtain distilled water at most grocery stores.
Purchase glycerine, which is safe to mix at home. Glycerine is available at many pharmacies. Ensure that you buy pure glycerine and not a sorbitol-based substitute. Sorbitol is a sugar and will burn when the fog machine heats it. Fog-machine fluid made with glycerine will form haze, not the thick, rolling fog that nightclubs require. Glycerin-based fog juice is most often used to provide haze effects for plays or Halloween parties.
Choose the appropriate mixture of distilled water and glycerin for the effect you want. A 5-percent solution of glycerin will produce a light haze; a 10-percent solution will provide a medium haze; and a 15-percent glycerin solution will make a heavy haze.
Pour the desired amount of glycerine into a clean plastic container and add the correct amount of distilled water. Close the container securely and shake it vigorously to mix the ingredients.