The explosion ranges of R134a/nitrogen/oxygen mixtures have been investigated at atmospheric pressure. The results of these full flammability tests at 20 degrees C and at 280 degrees C are presented in a triangular diagram. In addition, the influence of pressure on the flammability of R134a/air mixtures has also been studied. Under normal conditions, R134a is a non-flammable gas but exhibits an explosion range at higher oxygen percentages than those in air. At increased temperatures or pressures, R134a also has an explosion range in air, i.e. without any higher oxygen percentage. Using a detonation tube, the detonability of R134a/air mixture has been investigated for pressures between 8-20 bar and temperatures from room temperature to 200 degrees C. Stable detonations with detonation velocities of 1506-1535 m s(-1) were initiated by incoming detonation waves. For an oxygen-enriched R134a/nitrogen/oxygen mixture at 10 bar, using a glowing wire as the ignition source a pressure-piling effect was observed. In this experiment a pressure of more than 1200 bar was attained.