R-11, or Trichlorofluoromethane, was developed more than 70 years ago. In a class of gases known as "CFC's," it was found to be the most harmful of the "R" gases; it could damage respiratory systems if inhaled, and it could adversely affect the ozone layer, as well. Manufacturing of R-11 was discontinued after 1995, although it can still be purchased for home air conditioners. Here is a list of its most common uses prior to being discontinued.
R-11 was used in earlier refrigerating systems until the 1990s because it has a high boiling point; mechanisms within the refrigerator did not have to work as hard to keep the system cool. Since the R-11 allowed for a system of low-pressure, it alleviated strain on the mechanics of the unit. However, it was discovered that leaks could easily develop within the cooling system, releasing R-11 into the air and adding to ozone damage.
Known as "freon," R-11 is one of several refrigerants used in air conditioning systems. Because of the laws passed in various countries to make sure the gas does not produce any more harm, there are numerous procedures in place to recover, reclaim or recycle the R-11 when it is removed from an air conditioning system.
Gas turbine engines--jet engines--are found in most aircraft today, including military. These engines use large amounts of air, which are brought into the engine. A compressor increases the temperature and pressure of the air. This air is then mixed with fuel, causing it to ignite and turn into hot exhaust. This is passed through the turbine. As the exhaust heats, the engine does not work as efficiently, necessitating the use of a coolant. R-11 was the most common refrigerant used for this process until it was deemed unsafe.
