Learn more about Work interruption and Carpal Tunnel Syndrom

Hi, I don't know where else to ask these questions but could somebody help me answer them or point me to good literatures on work interruption and carpal tunnel syndrome?

1. What is the correct way to interrupt somebody in the middle of the work?

2. How do I ensure that the user is not really busy and would not mind being interrupted?

3. What kind of signals (sounds and visuals) do I provide to slowly guide the user from their working environment to the rest environment?

4. What kind of carpel tunnel exercise do people really not mind doing? Is there an appropriate time for a certain exercise? Should I tailor the exercise for different users?

Thank you.