leaks isobutane in the presence of a spark. If the coolant leaks into the fridge, at times when the door is not being opened (such as overnight) the concentration of coolant in the air within the fridge can build up to form an explosive mixture that can be ignited either by a spark from the thermostat or when the light comes on as the door is opened, resulting in documented cases of serious property damage and injury or even death from the resulting explosion. Disposal of discarded refrigerators is regulated, often mandating the removal of doors for safety reasons. Children playing hide-and-seek have been asphyxiated while hiding inside discarded refrigerators, particularly older models with latching doors, in a phenomenon called refrigerator death. Since 2 August 1956, under U.S. federal law, refrigerator doors are no longer permitted to latch and they can be opened from the inside. Modern units use a magnetic door gasket that holds the door sealed but allows it to be pushed open from the inside. This gasket was invented, developed and manufactured by Max Baermann (1903–1984) of Bergisch Gladbach/Germany. Regarding total life-cycle costs, many governments offer incentives to encourage recycling of old refrigerators. One example is the Phoenix refrigerator program launched in Australia. This government incentive picked up old refrigerators, paying their owners for "donating" the refrigerator. The refrigerator was then refurbished, with new door seals, a thorough cleaning and the removal of items, such as the cover that is strapped to the back of many older units. The resulting refrigerators, now over 10% more efficient, were then distributed to low income families. Gallery See also Auto-defrost Cold chain Continuous freezers Home automation Ice cream maker Ice famine Internet refrigerator KECO Industries, Inc. v. United States Kimchi refrigerator List of home appliances Pot-in-pot refrigerator Refrigerator death Refrigerator magnet Solar-powered refrigerator Star rating Water dispenser Wine cellar References Further reading Rees, Jonathan. Refrigeration Nation: A History of Ice, Appliances, and Enterprise in America (Johns Hopkins University Press; 2013) 256 pages External links Refrigerating apparatus Refrigerating apparatus The History of the Refrigerator and Freezers Refrigerators, Canada Science and Technology Museum 20th-century inventions Articles containing video clips Australian inventions Cooling technology Food preservation Food storage Heat pumps Home appliances Home automation Kitchen