9.1.1 These requirements have been formulated
principally for units having their hull superstructure, structural
bulkheads, decks and deckhouses constructed of steel.
9.1.2 Units constructed of other materials may
be accepted, provided that, in the opinion of the Administration,
they provide an equivalent standard of safety.
9.1.4 Windows and sidescuttles, with the exception
of navigating bridge windows, should be of the non-opening type. Navigating
bridge windows may be of the opening type provided the design of such
windows would permit rapid closure. The Administration may permit
windows and sidescuttles outside hazardous areas to be of the opening
type.
9.1.5 External doors in superstructures and deckhouses
should be constructed to "A-O" Class divisions and be self-closing,
where practicable.