[bxbb]

SharePoint is probably a good solution, considering your current workflow involving MS Word. Some features related to your problem:

- have revision support. A basic diff is available inside Word (Compare version).

- Breaking up the procedures as individual document can be done using outline view. Sub document can be created, imported from new files, or extracted from current master document.

- Co-authoring feature which enable multiple editors work on a same file, owner can review and accept/reject changes.

- Inventory management (I assume involving database) can be done using either Access or Excel.

What make SharePoint so nice is the Composites, which allow you to working with multiple datasource (Office files, SQL, Webservices). A handbook is available here: http://www.microsoft.com/en-us/download/details.aspx?id=3605...

Note: document outline doesn't require SharePoint (it's a built in feature of Word), co-authoring require either SharePoint or SkyDrive account to host the document.