Cameo Chemicals website states R404A is a mixture of CF3CHF2 (R125, 44 percent by mass); CF3CH3 (R143A, 52 percent); and CH2FCF3 (R134A, 4 percent). The gas is colorless and odorless, and a container of it may erupt violently when exposed to extreme heat.
This refrigerant blend's trade name is R404A. It's American Society of Heating, Refrigerating and Air-Conditioning Engineers number is 404A. The compound is listed as a zoetrope of near-azeotropic proportions.
Burns or frostbite may occur if skin is exposed to the gas. Since the gas is heavier than air, the gas spreads along the ground and may cause asphyxia. If ignited, toxic gases may be produced.