To take care of restrictions in the movement of personnel
and to limit the time needed for a possible emergency escape, two
separate means of access should be provided in double bottom tanks
and similar spaces where obstructions impede movement. The two accesses
should be as widely separated as practicable.
The provision of only one access may be approved in special
circumstances if the ability to readily traverse the space or to remove
an injured person can be proved to the satisfaction of the Administration.