The imidazole catalysed hydrolysis of triacetin has recently [1] been proposed as a test reaction for isothermal heat conduction microcalorimeters affording validation and traceability for results derived from these instruments. The published values for Delta(R)H(s) -91.7 + 3.0 kJ mol(-1) and for the rate constant at 298 K, k, 2.8 x 10(-6) +/- 9.7 x 10(-8) dm(3) mol(-1) s(-1), were the results from an international inter- and intra-laboratory study. The protocol [1] for the conduct of the reaction specifies the reaction composition and a temperature of 298 K. Here, we report the temperature and imidazole concentration dependence of the rate constant for this reaction and the derived value of the activation energy; E-a = 64.30 +/- 2.00 U mol(-1). The value of Delta(R)H is independent of temperature and a test for completeness of reaction (i.e. the reaction goes to completion at all temperatures and no effective equilibrium constant is determinable) is described.