Lloyd's Register Rulefinder 2020 - Version 9.33 - Fix
Statutory Documents - IMO Publications and Documents - International Codes - CTU Code - IMO/ILO/UNECE Code of Practice for Packing of Cargo Transport Units - Annex 2. Safe handling of CTUs

Annex 2. Safe handling of CTUs

 1 General

1.1 CTUs are designed for intermodal transport. They are capable to be transferred from one mode of transport to another by rolling or lifting. A swap body can be carried on a road vehicle or on a railway wagon. A freight container can be carried on a road vehicle, on a railway wagon, on an inland barge or on a seagoing vessel. A road vehicle can be carried on a railway wagon, on an inland barge or on a seagoing vessel (ro-ro ship). A railway wagon can be carried on a seagoing vessel (railway ferry).

1.2 When CTUs are handled, it should be ensured that all handling devices such as lifting appliances and internal movement equipment are in good condition and suitable for the intended purpose.

1.3 On completion of handling, CTUs should be secured to the means of transport as appropriate for the specific transport mode.

1.4 A CTU which is leaking cargo or obviously unsafe for further transport should not be loaded onto a means of transport.

2 Transfer by rolling

2.1 Swap bodies are carried by road on special swap carrier vehicles. The carrier vehicle is capable to be lowered on its wheels and to roll under the swap body standing on its supports. By lifting the vehicle to its normal operating position, the swap body is taken onto the chassis of the carrier vehicle. Then the support legs are retracted.

2.2 Road vehicles may be rolled onto a ship driven by their own engine. Semi-trailers are normally carried on board ships without tractor unit. They are loaded to and unloaded from the ships by specific port internal movement vehicles. These vehicles should be conspicuously painted or marked and fitted with a flashing or rotating yellow beacon. The drivers' cab should provide good all round visibility, with minimal obstruction of the driver's view. Only authorized persons should be allowed on the ramp or any vehicle deck while vehicle movements are taking place. The movement of persons on foot on the ramp should be strictly controlled and minimized.

2.3 The cargo decks of railway ferries are equipped with several rail tracks which can be accessed by a movable ramp which is fitted with rails, capable to be connected to the rail tracks on board. The maximum permissible kink angle between the ramp and the level of the rail deck in the ship is restricted and depends on the type of wagons shunted into the ship. In specific cases this angle may be as low as 1.5.

3 Transfer by lifting

3.1 Before lifting a CTU, the handling staff should ensure that the lifting equipment is safely attached to the CTU and that all securing, fixing and lashing devices have been released.

3.2 Swap bodies for combined road/rail transport and also purpose built semi-trailers for combined road/rail transport are equipped with standardized recesses for being lifted at four points by grappler arms attached to the spreader of a crane or reach stacker. Thus they can be transferred from road to rail and vice versa.

3.3 Lifting of freight containers (refer to ISO 3874)

3.3.1 The most appropriate method to lift a freight container is the use of a top lift spreader. The spreader is locked by twistlocks to the top corner fittings of the freight container. This method can be used for all freight container sizes fitted with top corner fittings, in an empty or packed state. When the spreader cannot be attached directly to the corner fittings, e.g. in case of over-height cargo, slings or chains can be used and connected to the spreader so that the lifting force remains vertical.

3.3.2 The side-lift frame is designed to lift a freight container by the two top corner fittings of one side and to take the reaction forces on the bottom corner fittings of the same side or on suitable corner post areas above those corner fittings. This method can be used on all sizes of empty freight containers. In the case of packed freight containers, this method is suitable for 20-foot and 10-foot freight containers only.

3.3.3 The end-lift frame is suitable only for the handling of 20-foot and 10-foot empty freight containers. The frame is designed to lift a freight container by the two top corner fittings of one end and to take reaction forces on the bottom corner fittings of the same end or on suitable corner post areas above those corner fittings.

3.3.4 A top lift sling can be used for empty freight containers of all sizes. The freight container is lifted by all four top corner castings with forces applied other than vertically. Lifting devices need to be properly engaged, hooks always be placed in an inward to outward direction. In the packed state, this method is suitable only for 10-foot freight containers, provided that the lifting forces are applied at an angle not less than 60 to the horizontal.

3.3.5 A bottom sling is used in connection with a cross beam spreader bar. The freight container is lifted from the side apertures of four bottom corner fittings by means of slings which are connected to the corner fittings by means of locking devices. Hooks are not suitable for this connection. This method can be used for all freight container sizes in an empty or packed state. For packed freight containers the angle between the sling and the horizontal should not be less than 30 for 40-foot freight containers, 45 for 20-foot freight containers and 60 for 10-foot freight containers.

3.3.6 When a freight container is provided with fork pockets, it can be lifted by means of forks under certain conditions. The forks should, ideally, extend the whole width of the freight container, but under no circumstances should they extend less than 1,825 mm into the fork pockets. This method can be used on 20-foot and 10-foot freight containers in an empty or packed state with the exception of tanks and pressurized bulk containers which should not be lifted by forklift trucks at all. Where there are no fork pockets, the freight container should not be lifted by forks in any state.

3.4 Railway wagons may be lifted and may change bogies when the railway ferry operates between countries where the gauge of the track is different. In such cases, the railway wagons should be suitable for an easy exchange of bogies. The involved ferry ports provide specific equipment for this operation.

4 Safety and security checks prior to entry

4.1 It is important for the terminal to ensure that CTUs accepted into the terminal are safe for operations and do not present a threat to the safety and security of the terminal, or ships and personnel within its environs. It is particularly important to ensure that "paperless" systems do not result in any dilution of the need to verify documentation.

4.2 The terminal should undertake the following actions at the first entry gate of the export yard, or while the CTU is in the terminal and before it goes onto a ship:

  • Match the carrier's documentation against that of the haulier in order to prevent fraudulent shipments;
  • Check the integrity of the CTU and its seal in order to preclude stowaways and the smuggling of contraband or threats to security. Whenever a broken or missing seal is found, it should be reported to the shipper and the authorities, and replaced with a new seal. The new seal number should be recorded;

  • Check the CTU number against documentation;

  • Check the presence of placards and markings on CTUs containing dangerous goods and verify them against documentation;

  • Verify the gross mass against documentation by use of a weighbridge or mass gauge/load indicator on yard equipment or, alternatively, verify that accurate gross mass determination has occurred before entry and that such determination was compliant with international requirements, where applicable, or accepted best practice;

  • Ensure, during the lifting of the CTU by any terminal equipment, that an evaluation is made by the operator to check that the mass of the cargo is reasonably evenly distributed. If it is determined to exceed the "60% within half the length rule", the terminal should take steps to rectify the problem;

  • Sideline any CTU that appears to be structurally unsound and/or unsafe for a more detailed examination;

  • Check the lashing of non-enclosed CTUs;

  • Confirm the dimensions of out of gauge cargo and update booking data accordingly;

  • Notify the CTU operator if out of gauge cargo is found to be improperly or inadequately secured to the CTU;

  • Check reefer temperatures against setting and, in cases where the allowable variance is exceeded, follow up with the CTU operator. A reasonable temperature variance should be set to trigger follow up action with CTU operators, and this should vary depending on the cargo type, i.e. chilled or frozen. If this is not possible at the gate due to a low battery, then the check should be made when the CTU is plugged into the terminal's power supply;

  • Check reefer plugs and wires for defects prior to plugging into the terminal's reefer system.

5 Stacking on ground and terminal operation with freight containers

5.1 The ground should be a firm, flat and drained surface. On the ground, the freight container should be supported by the four bottom container fittings only. When stacking freight containers, the bottom surfaces of the lower corner fittings of the upper freight container should have complete contact with upper surfaces of top container fittings of the lower freight container. A shift of up to 25 mm laterally and 38 mm longitudinally may be tolerated.

5.2 A freight container stack may be subject to forces by heavy wind. This might lead to sliding and toppling of freight containers. Stacks of empty freight containers will be more subject to such dangers than stacks of packed freight containers. The critical wind speed is higher for multiple rows than for a single row. Wind effect can be reduced by limiting the stacking height, by block stowage or by a combination of both. A recommended combination is shown in the table below:

Number of tiers 20-foot standard 40-foot standard 40-foot high cube
2 2 rows 2 rows 3 rows
3 2 rows 3 rows 3 rows
4 2 rows 3 rows 3 rows
5 3 rows 3 rows 4 rows
6 4 rows 4 rows 5 rows

5.3 Above recommendation is applicable for a wind speed up to 20 m/s (8 Bft). In case of higher wind speeds, additional measures should be considered, such as changing the block to a stepped pyramid or securing freight containers with lashings to the ground.

5.4 Freight containers should be moved within a terminal area only by use of suitable equipment, such as van carriers, reach stackers or trailers. Trailers should be so constructed that the freight containers are supported by their corner fittings. For operation within the designated terminal area, tie down devices are not required, provided that the freight container is correctly loaded on the trailer and prevented from moving horizontally. Therefore, trailers which are not equipped with twistlocks should be fitted with substantial corner plates or other restraints of sufficient height to retain the freight container in position.

6 Securing of CTUs

6.1 Swap bodies are carried by road on dedicated carrier vehicles. The corner fittings of the swap body fit onto cones of locking devices (twistlocks) which, by turning the cones, provide a form closure between the swap body and the vehicle structure (see figure 2.1).

Figure 2.1 Twistlock on a road vehicle

6.2 Freight containers should be carried by road on purpose built container chassis, where the freight container is supported by the four corner fittings. The corner fittings of the freight container fit onto the twistlocks cones of the chassis, similar to the securing devices described in 6.1.

6.3 When carried by rail, swap bodies and freight containers are loaded on open wagons which are specifically fitted with stacking or locking devices. Semi-trailers may be carried on wagons equipped with dedicated bedding devices for accommodating road vehicles.

6.4 Container vessels are specifically constructed for the carriage of freight containers. Cargo spaces under deck or cargo spaces on hatchless container vessels are equipped with cell guides, where the freight containers are stacked, obtaining sufficient hold and securing. 20-foot freight containers may be stowed in 40-foot cell guides, provided that suitable stacking cones are inserted into the corner fittings of the freight containers. Freight containers carried on deck are affixed to the ships structure by means of twistlocks. Twistlocks are used also to interconnect freight containers stowed one on top of another. In addition, container stacks on deck are secured to the ships structure by means of lashing rods and tensioning devices (bottle screws) (see figure 2.2). Details of the securing arrangement are described in the Cargo Securing Manual of the individual ship.

Figure: 2.2 Cell guides and lashing rods on a container vessel

6.5 When carried on general cargo ships which are not specifically constructed for the carriage of freight containers, the freight containers are secured to the ships structure by means of lashing chains or wire ropes and tensioning devices (see IMO Code of Safe Practice for Cargo Stowage and Securing, Annex 1). Further details are described in the Cargo Securing Manual of the individual ship.

6.6 When vehicles are loaded in a vehicle deck of a ro-ro ship, the parking brakes should be applied and locked, engines should be in gear. Uncoupled semi-trailers should not be supported on their landing legs but preferably supported by a trestle or similar device. Lashings which are attached to the securing points of the vehicle should be connected with hooks or other devices so designed that they cannot disengage from the aperture of the securing point if the lashing slackens during the voyage. Only one lashing should be attached to any one aperture of the securing point on the vehicle. Further details are described in the Cargo Securing Manual of the individual ship.

6.7 The wheels of railcars shunted into the rail deck of a railway ferry should be chocked on the rail with appropriate steel chocks. The wagons should be secured to the ships structure with chains and tensioning devices (bottle screws). In case of severe weather conditions, the spring system of the wagons should be released by use of specific trestles. Further details are described in the Cargo Securing Manual of the individual ship.


Copyright 2020 Lloyd's Register Group Limited, International Maritime Organization, International Labour Organization or Maritime and Coastguard Agency. All rights reserved. Lloyd's Register Group Limited, its affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as 'Lloyd's Register'. Lloyd's Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant Lloyd's Register entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.