Re: Unattached forms
I am not sure what your question is regarding so I will answer to the best of my ability hoping I hit your question.
1. Forms (not filled out) are part of document control (4.2.3). In essence, these need to be controlled to prevent unintended use, legible, identifiable, and relevant. We have all forms logged in an excel file (because we are old fashion) with form number, revision, who is responsible, and who it applies to. We ended up 'controlling' some forms that seemed, at the time, to be silly such as vacation requests, person tool purchases, and the like. However, it was pointed out that these fall under 6.2 so we gave them identifications. (Note: I still disagree that things like Vacation requests, and office supply request forms should be on this list but I was the loser in this argument).
2. If you are talking about records (form is filled out) that falls under 4.2.4 and must be maintained for the duration. You and/or your customer define the time. For example, material certifications per our customer must be maintained for 2-10 years (depending on customer) so we just maintain all material certifications for 10+ years. Vacation Requests are stored for 1 year after the vacation is taken (we defined this time).
I hope this helps.