Characteristics of refrigerants

In the presence of an open flame freon decompose to form toxic products, most of which has a characteristic odor even at low concentrations. Freon 12, 13, 13B1, 22, 115, 502 at high concentrations cause suffocation from lack of oxygen. Halocarbon 21 at high concentrations has a narcotic effect. Refrigerant 502 does not have a warning odor and has no borders between non-toxic and life-threatening concentrations.
 Refrigerants recommended to replace R12
ODP – the rate of destruction of the ozone layer relative to ferrichloride R11
GWP  - indicator of global warming relative to carbon monoxide in the billing period 100 years
Freon 134a is a colorless gas, is one of the first refrigerants, which was made without the use of chlorine.  Safe  non-toxic and non-flammable at all temperatures. Most often, this refrigerant is charged automotive air conditioners, refrigeration compressor equipment, industrial and residential use.Used for the manufacture of other brands of freon. 
Freon R12 refers to a group of chlorofluorocarbons. Colorless gas with a characteristic odor. One of the most common and safe to use refrigerants. Non-explosive,  t > 330 °C decomposes to form hydrogen chloride, hydrogen fluoride and traces of toxic gas phosgene.  Characterized by fluidity, which facilitates its penetration through the smallest leaks. At the same time due to the increased turnover of R12 refrigeration compressors oils penetrate through all rubbing parts, reducing wear. When volume concentration  in the air more than 30 % comes suffocation from lack of oxygen. Soluble in oil,  poorly soluble in water. Used in single-stage refrigeration parts machines with a dew point of not more than 75 °C and a boiling point not lower than -30 °C, in apartment refrigerator, air conditioners. Replace : R134a, R401b, R401c, R406а, R413a, R600a.
Freon R22 - inert chemically, non-flammable, non-explosive liquid under pressure,a gas. Under normal conditions Freon R22  it is a stable substance, which under the influence of temperatures above 400°may decompose with the formation of highly toxic products: tetrafluoroethylene , hydrogen chloride , hydrogen fluoride . When heated  more than 250 deg. Celsius formed a very poisonous products such as phosgene, COCl2, which in the first world war it was used as a fighting toxic substance.  is Used as the refrigerant in the medium and low temperature refrigeration systems industrial, commercial and domestic equipment.
Freon  R 600 and. Chemical formula of Freon R 600 a - SN (isobutane). Freon R600 is a natural gas, so it does not destroy the ozone layer  and does not contribute to the emergence of the greenhouse effect . These characteristics R600a has a significant advantage over Freon R12 and R134a Freon. The mass of refrigerant in the refrigeration unit when using isobutane, is greatly reduced (about 30%). Unit weight of isobutane 2 times more specific mass of air in the gaseous state Refrigerant R600a trails on the ground. Isobutane is soluble in mineral oil and has a higher coefficient of performance than Freon R12, which reduces energy consumption. Used in refrigeration appliances and mobile room air conditioners. Store  R600a should at a temperature of not higher than -20 ° C, avoid exposure to direct sunlight, away from open flame.  Isobutane flammable, easily flammable and explosive, but only when interacting with air at a volume concentration of the refrigerant from 1.3 to 8.5%. The lower bound explosive™ (1,3%) corresponds to 31 g R600a 1 m3 of air; the upper boundary (8,5%) 205 g R600a 1 m3 of air. Flash -460°C.
Refrigeration units with R600a are characterized by lower noise levels due to low pressure in the working refrigerant circuit. as in refrigeration units R600a is used in minimal quantities, it is not required to be disposed of, the remaining refrigerant remains dissolved in the oil. Refrigerant R600a is not harmful to the environment. the Use of isobutane in existing refrigeration equipment associated with the need to replace the air compressor attachments on the compressor greater productivity, because in specific volumetric cooling capacity R600a is losing refrigerant R12 (almost twice). Due to the high energy properties, R600a, the amount of refrigerant charged into the refrigeration unit, is reduced compared to R12 approximately 60 %. Together with the rate of charging is reduced and the tolerances, resulting in the refrigeration unit should be refilled R600a carefully. Recommended oils Mineral: HP-16, Mobil Gargoyle Arctic Oil 155 , 300, Suniso 3GS and 4GS. 
Freon R410a -  quasiisotropic mixture of R125 and R32,  leakage practically does not change its composition,  equipment may just be refueled. Non-flammable gas. When in contact with flames and hot surfaces decomposes to form toxic products. Contact with certain active metals under certain conditions (e.g. very high temperatures and/or pressure) may cause explosion or fire. Is a replacement for R22, is designed for the filling of new air conditioning systems high pressure.

R410a keeps its performance is much longer than that of R22. Specific R410a cooling capacity by about 50% greater than that of R22 (when condensation temperature of 54 ° C), and the working pressure in the cycle 35-45% higher than that of R22, which leads to the necessity of making design changes in equipment,  R410a cannot be used as a retrofit (replacement) of the refrigerant for R22.