Open the Share dialog from a worker's card in the Directory (or their profile) — the share icon opens a QR code, copyable link, and two controls that govern whether that link actually works.
Public view toggle
This switches the record on or off immediately. Turn it off and the link stops resolving right away — anyone visiting it (including via a previously printed QR code) sees "This record isn't available." Turn it back on and the same link works again instantly; the underlying slug never changes, so you don't need to reprint anything.
Link expires
Set the link to expire never, or automatically in 7, 30, or 90 days from whenever you set it. This is enforced on the server, not just hidden in the UI — once the date passes, the link stops resolving the same way a manually disabled one does.