Posted By Denis Hands You are quite correct in what you say about vibration levels increasing as tools wear, but what you should also be aware of is that some manufacturers of rotating and percussive tools base the declared vibration measurement for their products on laboratory simulation and not field trials. Of course, this gives totally unrealistic low vibration figures which cannot be achieved in use. Vibration measurement is an activity that requires expensive specialist equipment. The way I see it you have two choices. Either go on a vibration management and maesurement course to learn the practical techniques and be prepared to purchase the equipment required, or hire in vibration specialists who will carry out your testing for a fee. A company called Industrial Noise and Vibration Centre Ltd run an excellent two day vibration management and measurement course that is accredited by IOSH. Their telephone number is 01753 698800