Seems good to me. What does the Many-to-Many comment mean?
Your "middle table" which you are calling EquipmentRegister, is a junction table that is used to resolve many to many.
You can have lookup tables as mentioned previously to facilitate some of the services and attributes.
Do you deal with multiple buildings and/or multiple floors? Where are your Categories?
My "Many-to-Many" comment was just part of the notes i kept jotting down, i managed to crop most of them out.
Multiple floors and buildings yes, but this information is not required for what we are producing. I have my catagories/classification/department as drop down boxes as they will be based on client information which never changes or added to. I didnt show them on this data model as they didnt relate to the equipment and i ran out of space.
My next task once ive finished this DB is to look at BIM (Revit in particular) and Access working together.