The present invention relates to hand held tool monitoring apparatus (10). The hand held tool monitoring apparatus (10) comprises a mount, which in use of the hand held tool monitoring apparatus forms part of a hand held tool (22), and a monitoring component (12) configured to be releasably attached to the mount. The monitoring component (12) comprises an operative part of the hand held tool monitoring apparatus (10) and the hand held tool monitoring apparatus further comprises a vibration sensor and a timer. The vibration sensor is operable to sense vibration of the hand held tool (22) and to provide a vibration signal in response to sensed vibration when the monitoring component is attached to the mount. The timer is operative in dependence on the vibration signal to record a duration of vibration of the hand held tool (22).