中文摘要：

分析了R245fa的阻燃，试验研究了R245fa在电打火（点火能约为100J）和普通打火机点火两种条件下对R290、R152a、DME、R600a的阻燃特性，提出了新的评判阻燃组分阻燃特性强弱的指标（阻燃系数K），并对R245fa作用于各可燃工质的阻燃效果进行分类．试验结果表明，点火能大小、点火源形式对可燃工质燃爆极限影响很大；R245fa对碳氢类可燃工质阻燃效果差；对HFC类的阻燃效果相对较好；R245fa的阻燃效果比R134a的差．

英文摘要：

The flame-retarding mechanism of 1,1,1,3,3-pentafluoropropane （R245fa） were analyzed. Under conditions of an electric ignition, with energy of about 100 J and an ignition with a common lighter, the fire-inhibiting characteristics of R245fa on propane （R290）, difluoroethane （R152a）, dimethyl ether and isobutene （R600a） were studied in tests. A new index of flame-retarding coefficient , K, that evaluated the flame-inhibiting effect of refrigerants was put forward. Based on this index, the flame-retarding effectiveness of R245fa on flammable refrigerants was classified. The result shows that flammable limits of refrigerants are greatly affected by the ignition energy and mode, the inhibiting effectiveness of R245fa on hydrofluorocarbons refrigerants was bad but better than on hydrocarbons, and the flame-retarding effectiveness of R245fa was worse than that of 1,1,1,2-tetrafluoroethane （R134a）.