Are you talking about that form 28 thing? I can't imagine that most TSOs filled out 40 pages of paperwork to get hired. Are you talking about the thing for Secret Clearance?
What you're describing sounds like the form for an SSBI and that isn't done on all TSOs.
It does sound like the SF-86 (or the current online version). The TSA wouldn't want to pay for either Secret or TS clearances for screeners that have heavy turnover.
This report tells more.