Normally Access won't let you open the same form more than once.
Double-clicking on the form, or issuing the statement DoCmd.OpenForm, just
sets the focus the copy of the form that is already open. There's a way in
code to open multiple instances of the same form, but that takes special
coding. Are you doing something where multiple open instances of the same
form are causing a problem?
It is true that you could easily have multiple copies of the same form open
as subforms on other forms. Is that what you are concerned about?