This paper reports the design and implementation of a system based on a wireless sensor network for measuring the temperature and pH in a tannery barrel. The prototype consists of a base node and two battery-powered remote sensor nodes. These sensor nodes are responsible for performing the measurements and transmit them via multi-hop radio links to a PC-connected base station. The system includes a user application running on a PC that can store and display data, and monitor and configure the system. The analysis of experimental data obtained in tests in the industrial plant shows that the system is capable of measuring pH in the range of 2 to 8 with an uncertainty of 0.1 pH, and temperature in the range of 10 C to 70 C with an uncertainty of 0.5 C. The main contribution of this work consists in adapting a system based on a wireless sensor network to an industrial environment.