(a) Each tankship must have portable ventilation equipment that fits the mount required in paragraph (b)(1) of this section.
(b) Each enclosed space within the cargo area that does not have a permanent ventilation system meeting § 153.312 must have:
(1) A mount for the portable mechanical ventilation equipment required by this section; and
(2) Either permanent ventilation ductwork connected to the mount and arranged to supply air to the extremities of the space; or
(3) An attachment for temporary ductwork at the mount with enough ductway in the ventilated space and temporary ductwork stowed aboard the vessel to supply air to the extremities of the space.