[en] The influence of impurity concentration c and applied magnetic field H on the superconducting transition of high-purity commercial titanium samples was investigated. The superconductive transition temperature T_C was found to be very sensitive to the impurity concentration (dT_C/dc ∼ -0.6 mK/w.ppm) and to the applied magnetic field (dT_C/dH) ∼ -1.1 mK/G). A linear dependence of T_C decrease on impurity concentration, as theoretically predicted by various authors, was observed. In the purest sample, a linear decrease of T_C on the applied magnetic field was found. The run-to-run and sample-to-sample reproducibility of the transition of the same sample was evaluated, and its suitability as a thermometric reference point below 1 K was discussed