Maximum temperature of reactant mixture is an important parameter regarding reactor safety. If the control of reaction temperature is lost, then side or decomposition reactions may be triggered leading to thermal runaway situation. This study concerns a liquid phase reaction system. This paper explores the influence of parameters on the thermal safety of a pilot tubular reactor. The following parameters were studied: the inlet temperature of the coolant, the volumetric flow rate, and the co-current flow and the counter-current flow configurations. The aim was to identify the main parameters that control the reaction temperature in the presence of a fast exothermic reaction system. The results showed that co-current configuration allows to control the maximum temperature. By changing the configuration, the cooling power can be reduced compared to a change in the inlet temperature of the coolant. A criterion of stability has been implicated in order to confirm this result.