In a chemical plant, a technician observed reddish smoke released from a pump assembly being used to drain 30-kg barrels containing a raw material (a chlorine-bromine polymer in solution with perchloroethylene). A supply shortfall of this solution packed in bulk led to using these 30-kg barrels. The technician halted transfer and cooled the pump by sprinkling to avoid any ignition. The accident resulted from heating the pump shaft after repeated discontinuous loadings due to a raw material leak that went undetected at the level of the stuffing box, caused by an opaque pump casing. The pump needed to be replaced, triggering a 2-hour shutdown of the production chain. Damage was appraised at €1,000, and several measures were adopted: implementation of a preventive maintenance programme, replacement of the damaged pump, and installation of a latticed casing for all pumps in the concerned workshop in order to facilitate the detection of eventual leaks and enhance shop personnel awareness. These various actions were to be verified during an inspection held on 25th May. Other measures were anticipated, namely the installation of latticed casing whenever “sensitive” products were used (i.e. easily polymerised, in bulk quantities, highly viscous), modification of the “change review” procedure dating from 2004 by including comments on the problem highlighted at the time of this incident or by completely rewriting the review and taking into account complementary actions.