Refrigerants with lower GWP are preferred in order to mitigate their climate impact. Lower GWP generally means shorter life in the atmosphere.Thus most of the proposed alternatives are flammable or toxic, since they are less stable in air. To ensure they can be used appropriately a precise assessment of their flammability risks is necessary. The old methods of assessing flammability do not accurately represent the hazards faced, so a newindex, Burning Velocity, has been introduced. Based on the flammability of ammonia with this index a new flammability class “2L” is proposed in the current ISO817 draft. This presentation gives the key characteristics of the new index and describes the combustion behaviour of 2L refrigerants. |
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