AS 3711.4:2015 Freight containers
5.3.2.3 The transfer of load between the underside of the bottom side rails and carrying vehicles is not envisaged. The transfer of load between side rails and handling equipment should only occur when provisions have been made in accordance with 5.8.1 and 5.8.2.
5.3.2.4 Containers having all their intermediate transverse members spaced at 1 000 mm apart or less (or having a flat underside) shall be deemed to comply with the requirements laid down in 5.3.2.1.
5.3.2.5 Requirements for containers not having transverse members spaced 1 000 mm apart or less (and not having a flat underside) are given in Annex B of ISO 668:1995.
5.3.3 For containers 1 D and 1 DX, the level of the underside of the base structure is not specified, except in so far as it is implied in 5.3.4.
5.3.4 For all containers under dynamic conditions, or the static equivalent thereof, with the container having a load uniformly distributed over the floor in such a way that the combined mass of the container and test load is equal to 1,8 R, no part of the base of the container shall deflect more than 6 mm below the base plane (bottom faces of the lower corner fittings).
5.3.5 The base structure shall be designed to withstand all forces, particularly lateral forces, induced by the cargo in service. This is particularly important where provisions are made for securement of cargo to the base structure of the container.
5.3.6 1EEE and 1EE units shall have recesses longitudinally-outboard of each of their fittings in the 1 AAA/1 AA/1 A position. These recesses shall extend vertically to not less than 76 mm above the plane of the bottom faces of the fittings in the 1 AAA/1 AA/1 A position, shall extend longitudinally from the longitudinally outboard faces of the fittings in the 1 AAA/1 AA/1 A position outboard, to not less than 254 mm from the centrelines of the bottom apertures of the fittings in the 1 AAA/1 AA/1 A position and shall extend laterally from the external width of the container inboard not less than 154 mm. See Figure 1.