Refrigerant R1234YF Combustibility/Decomposition

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The refrigerant R1234yf is combustible in a specified concentration in the surrounding air.
The refrigerant R1234yf breaks down when exposed to flames and glowing or hot surfaces. UV light also causes refrigerant decomposition (UV light is a component of normal sunlight, it is also created for example by electric welding) the resulting decomposition products are toxic and must not be inhaled. However, irritation of the mucous membranes provides an adequate and timely warning.
During decomposition specific dangerous products such as carbon monoxide, hydrogen fluoride and/or hydrocarbons can be created.