CFC - The 1st Generation of Refrigerant Gases

Refrigerant Gases were born in 1834, after the French physicist formulated his theories about refrigeration cycle.

At the beginning of the XIX century, only "natural" fluids were used: water, ammonia, sulfur dioxide, carbon dioxide, nitrous oxide, ethane and propane.

In the '30, hazards in using those fluids drove operators in the field to use new types of refrigerant characterized by a higher degree of safety when used; In particular, chlorinated fluids such as Freon 11 and Freon 12 spread on the market. In that period it was preferred the use of fluids that were chemically stable, with good thermodynamic properties, non-toxic and non-flammable; Chlorine and fluorine were the chemical elements that guaranteed such requirements. The 1st Generation Refrigerant Gases - CFC - were made for the most part from those elements.
HCFC - The 2nd Generation of Refrigerant Gases

In the '80 the two american scientists Rowland and Molina presented a new theory showing that the chlorine contained in the CFC gases causes damages in the athmospheric ozone layer. The refrigerant industry was deeply involved in such situation; Environmental care required the elimination of chlorine which until then constituted the strong point to achieve the required features of refrigerant fluids.

In 1987, the Montreal Protocol established the progressive decrease in use over time of CFC, up to the complete suspension of their production in 2000.

In the meantime, 2nd generation refrigerant gases - HCFC - came into use, such as R22 and R502. HCFC gases are CFC gases where chlorine particles are partially replaced with hydrogen, so to make the molecules unstable when in contact with the atmosphere; as a consequence thay tend to decompose very quickly reducing the detrimental effect on the ozone.
HFC - The 3rd Generation of Refrigerant Gases

In HCFC gases, hydrogen only partially replaces chlorine; thus, European regulations 549/91 and 3952/92 ratified the early stop of CFC production and the progressive retirement of HCFC; 3rd generation HFC gases were then born, refrigerant fluids where chlorine particles are completely replaced by hydrogen. In 1998, the Kyoto Climate Change World Conference banned HFC refrigerant because even though they don't present the detrimental effect to the Ozone layer, they contribute to the Greenhouse Effect.

On 5th of May 2000, the European regulation 2037/2000 comes to pass which, with the following changes introduced by the European regulation CE 1005/2009, further disciplines HCFC and HFC disposal program.

In 2001, the Italian Environment Ministry published the decree D.M. Ambiente - 3/10/2001, that estabilished the obligation to collect and disposal of chlorofluorocarbon still present in various systems. Further, in 2006 the European union ratifies the 842 F-GAS regulation that dictates a periodic control of systems to prevent the risk of leaks and set a limit to phase-out HFC with GWP > 150 in car conditioning.