Welcome to the forum Steve.

In my opinion DB2006(05) is as good a working document as you're likely to get as "official guidance" in the UK.
But (as Neil hints at above):- policy without compulsion (enforcement?) is simply an exercise in wishful thinking!
Bottom line advice? Follow the document, then "report back" (up the food chain) if you find it lacking in any way.
But obsolete? I would have thought not. Good equipment management practice(s) don't change that much.