4.—(1) Paragraph (2) applies to any passage or other area affording a means of escape from station premises in case of fire or giving access to such a means of escape.
(2) Every door which does not form part of, or give access to, the means of escape must be kept locked at all times when the part of the premises to which the door gives access is neither in use by any person who is at work in the premises nor available for use by members of the public.