f90-mode-hook

f90-mode-hook is a variable defined in `f90.el'.
Its value is

nil

• This variable may be risky if used as a file-local variable.
• This variable is safe as a file local variable if its value
  satisfies the predicate which is a byte-compiled expression.
  

Documentation:
Hook run after entering F90 mode.
No problems result if this variable is not bound.
`add-hook' automatically binds it. (This is true for all hook variables.)

You can customize this variable.