At my field the following must be in place before LVP can be in force:
-All gates must be closed and keys accounted for
-All LVP-warning lights for vehicles on
-All vehicle movement on the manouvering area suspended
-RWY & TWY lights on
-Backup power generator on
-ILS CAT II/III-protected zone clear (CAT II/III-holding points in use)
-Stopbars on
-ATIS transmits LVP in force.