A theater fog machine is generally a 30 to 55-gallon metal or plastic water barrel with a 110-volt or a 220-volt hot water heater to keep the water hot. Dry Ice is placed in a bucket with holes to allow hot water to enter. When the bucket is lowered into the hot water fog is instantly produced. The resulting water vapor fog is gently blown by a fan and directed to the desired area by an air duct tube. Fog stops whenever the bucket of Dry Ice is pulled out of the water. More recent fog machines pump heated water over a trey holding the Dry Ice. All have a GFCI breaker for safety.