A security rail is simply a 3" aluminum flat bar welded to the side rail of the gangway. It helps "close in" in the sides. The typical use is with a ADA or intermediate handrail.

This photo shows one row of security rail on a heavy-duty gangway across a raven at a golf course.

This gangway is located in the Segway test facility. The security rail was place at a height to assure the wheel would not jump the curb.

Four rows of security rail were added to these gangway located at Mystic Seaport, in Mystic Connecticut.

This picture shows a residential gangway application, the customer choose two rows of security rail.