A re-usable sensor module for use with a dispenser for a hand hygiene product is described, wherein the dispenser comprises a container. The sensor module comprises an elastically deformable capsule with a top portion for placing a bottom of the container thereon. A sensor is arranged within the capsule and configured to measure a parameter associated with an elastic deformation of the capsule resulting from actuation or presence of the dispenser. The sensor module further comprises a processor arranged within the capsule and coupled to the sensor. The processor is configured to at least temporarily record at least one of the parameter and an event associated therewith.