In this study, lower flammability limits (LFLs) of three hydrocarbon refrigerants (R600a, R290, R1270) and two hydrofluorocarbon refrigerants (R152a, R32) and DME (RE170) are measured by the method proposed by ASTM E681-04 Standard. Flammability tests are carried out at three temperatures of $23^{circ}C,;60^{circ}C;and;100^{circ}C$ and relative humidity 50%. Test results show that the present data for isobutane and propane obtained at $23^{circ}C$ are similar to those found in the literature, confirming indirectly the reliability of the present test method and facility. For propylene, R152a, and R32, LFLs found in the literature differ considerably. Especially, the deviation of LFL of propylene is more than 30% among the literature data. The present data for propylene, R152a, and R32 agree with either of the data sets available. As the temperature increases from $23^{circ}C;to;100^{circ}C$, LFLs of all refrigerants tested decrease. LFLs of most refrigerants tested in this study at $60^{circ}C$ decrease by $0.1{sim}0.3%$ as compared to those at $23^{circ}C$. Also LFLs of most refrigerants tested in this study at $100^{circ}C$ decrease by $0.1{sim}0.3%$ as compared to those at $60^{circ}C$.