How do we keep track of upgrades / changes?

Layout and electrical circuits of the LHC machine are well documented in the databases and the data has been used throughout hardware and beam commissioning. During the shutdown a number of changes will be made all around the accelerator, to different systems. The presentation will address in what areas changes are expected and how the changes are (or are not) documented. Proposals will be made how to record and track the changes in order to avoid to use data that does not correspond to the as-built status when restarting the machine in Spring.