Drawbacks of duplication

I’m not disputing that CRB checks and attending safeguarding courses are very important and whilst having specific guidance for each organisation is useful, it can be frustrating having to duplicate all of these things, particularly when people work with children in lots of different situations (schools, Brigades , church etc.) It also means that people who have already attended such courses become more reluctant to volunteer when it means they have to attend another, effectively duplicating much of what they have already done. Surely, there must be a better way of doing things, whilst still ensuring children are kept safe?