Firstly, thanks to all for the great replies. Please keep em coming.
Eng AW139:
That system might work in the maintenance shop . What I am looking for is how to monitor tools of a single mechanic at a base working autonomously. Everyone has their own system and it has worked so far.But that is out of luck rather than a system. The region I work in wants to standardize the procedure and has given this to me as a project. I am also getting inputs from the mechanics concerned but I just thought it would be good to throw out a wider net.
Alt3