Cargo stowage in accordance with the CTU Code – securing rules, requirements and the shipper’s liability

Cargo stowage involves the arrangement and securing of goods within a transport unit – a container, semi-trailer or railway wagon – so that they can withstand all the forces acting upon them during transit. The international benchmark for this work is the CTU Code, the IMO/ILO/UNECE code of practice on the packing of transport units. Formally, it is not mandatory, but it is on the basis of this code that shipowners, insurers and surveyors assess whether the cargo has been secured with due care. And when something shifts inside a container sealed by the consignor, liability rarely falls on the carrier. According to estimates by the Cargo Integrity Group, poor packing practices cost the transport industry over US$6 billion a year. Below, we explain what the CTU Code requires, what forces act on the cargo on different routes, who is responsible for the consequences of errors, and what data you need to prepare before commissioning container stowage.

What is a CTU Code, and is it compulsory?

CTU Code – full name: IMO/ILO/UNECE Code of Practice for the Packing of Cargo Transport Units – was drawn up jointly by three organisations: the International Maritime Organisation (IMO), the International Labour Organisation (ILO) and the United Nations Economic Commission for Europe (UNECE). The Code replaced the previous guidelines from 1997, and the IMO published it in Circular MSC.1/Circ.1497 of 16 December 2014.

This applies to all cargo transport units (CTUs): containers, swap bodies, semi-trailers, road vehicles and railway wagons. It covers the entire intermodal chain – from the consignor’s warehouse, via road, rail and sea, right through to unloading at the consignee’s premises. This is important in practice: a container stowed ‘for shipment’ must also be able to withstand transport by lorry to the port and any subsequent rail journey.

The legal status of the code is sometimes a source of misunderstanding. The CTU Code is a set of recommendations, not a legal provision – it explicitly states that it does not replace national or international regulations. Nevertheless, in the event of damage, it is against this Code that the method of packing and securing the cargo is assessed. An expert, an insurer or a court will not ask whether the Code was mandatory, but whether the cargo was secured in accordance with recognised practice.

A new version of CTU Code is in the pipeline

The IMO, ILO and UNECE are working on a revised edition of the Code. The draft introduces a four-tier structure: a core level containing general principles, and technical levels that can be updated more frequently without the need to revise the entire document. In accordance with the timetable adopted at the MSC 111 session, the new version is due to be submitted for approval by the IMO Maritime Safety Committee at the MSC 112 session in December 2026.

The basic principles – securing the load against foreseeable forces during transport, the allocation of responsibility within the supply chain, and the documentation of packaging – remain unchanged. A company that currently packs in accordance with the 2014 edition therefore does not need to overhaul its practices from scratch.

CTU Code, EN 12195-1 and CSS Code – how do they differ?

Three documents frequently come up in discussions about load securing. Each one covers a different area:

• CTU Code – the interior of a transport unit, i.e. the stowage and securing of goods within a container, semi-trailer or railway wagon. This is the responsibility of the packer and the consignor.
• EN 12195-1 – the European standard on the securing of loads in road vehicles and the calculation of lashing forces.
• IMO CSS Code (Code of Safe Practice for Cargo Stowage and Securing) – the stowage and securing of cargo on board a ship, which falls within the remit of the shipowner and the crew.

For a consignor sending goods in a container, the CTU Code is the most important, as it covers all modes of transport through which the packed unit will pass.

Who is responsible for stowing the container? The chain of responsibility

The CTU Code does not point the finger at any one person – it describes a chain of roles, each with its own responsibilities.

Role	Who is it usually?	Main duties according to the CTU Code
Consignor	The party preparing the consignment, e.g. the machine manufacturer	Accurate description of the goods and their weight, packaging designed to protect the load, information on dangerous goods
Packer	The company or department that physically loads and secures the goods	Checking the condition of the unit, ensuring the load is correctly positioned and supported, securing it against forces during transport, and closing and sealing it
Shipper	The party named in the bill of lading or party to the contract of carriage	Selecting the appropriate container for the cargo and route, declaring the cargo and the verified gross mass (VGM), and handing over the documents to the carrier
Carrier	Shipowner, rail or road operator	Handle the unit with care; secure the unit itself on the means of transport
Consignee	The company receiving the consignment	Inspection on delivery, reporting of damage, unloading and cleaning of the vessel

The key sentence is found in clause 4.1.2 of the code: the shipper remains liable for any defect in the transport unit resulting from the cargo being poorly packed and secured.

In practice, a single company often fulfils several roles at once. The machine manufacturer may also act as both the consignor and the loader, whilst outsourcing the actual packing and stowage to a specialist contractor. In such cases, the division of responsibilities between the manufacturer and the packer is set out in the contract – and it is worth putting this in writing before loading, rather than after the event.

The sender’s liability under the law

Transport regulations consistently shift the consequences of poor packaging onto the party responsible for it:

• Maritime transport. Pursuant to Article 165(2) of the Maritime Code, the carrier shall not be liable for damage resulting, inter alia, from ‘inadequate packaging’ (point 11) and from “the acts or omissions of the charterer, shipper or consignee” (point 14). The carrier usually accepts an FCL container sealed by the shipper without inspecting the contents, with a clause in the bill of lading such as ‘shipper’s load, stow and count’.
• International road transport. The CMR Convention (Article 17(4)(b) and (c)) exempts the carrier from liability where the damage results from the absence or defectiveness of the packaging, or from the loading, stowage or unloading of the goods by the consignor. In turn, Article 10 of the CMR holds the consignor liable to the carrier for damage caused to persons, equipment or other goods by defective packaging – unless the defect was apparent or known to the carrier at the time of acceptance of the goods, and the carrier did not raise any objections.
• Domestic transport. Under Article 43 of the Transport Act, loading and unloading operations are the responsibility of the consignor or consignee, unless otherwise provided for in the contract or by specific legislation.
• Container weight. From 1 July 2016, the SOLAS Convention (Chapter VI, Regulation 2) requires the shipper to provide the verified gross mass (VGM) of the container. Without this, the container will not be loaded onto the ship. The mass is determined either by weighing the packed container or by adding together the masses of the entire contents, the dunnage and the container’s tare weight.

Cargo insurance won’t fix poor stowage

Many shippers assume that any damage will be covered by a cargo insurance policy. However, clause 4.3 of the standard Institute Cargo Clauses (A) 2009 excludes damage caused by insufficient or unsuitable packaging or preparation of the cargo for ordinary incidents in transport – if the packing was carried out by the insured or their employees, or if it was done before the insurance cover commenced. The clause explicitly includes stowage within a container as part of ‘packaging’. It is worth checking the scope of exclusions in your policy, but the general conclusion is clear: insurance is no substitute for proper securing of the cargo.

What forces act on the load? Accelerations according to the CTU Code

The CTU Code describes the forces acting on the load as accelerations expressed in g. A value of 1 g corresponds to the weight of the load. So, if the code specifies 0.8 g forwards for road transport, this means that when a lorry brakes suddenly, a force equal to 80 per cent of the load’s weight acts on it, pushing it towards the cab.

Means of transport	Forward	Backwards	To the sides	Vertically (pressure on the floor)*
Road transport	0.8 g	0.5 g	0.5 g	1.0 g
Rail transport (intermodal)	0.5 g (1.0 g)**	0.5 g (1.0 g)**	0.5 g	1.0 g (0.7 g)**
The sea – Area A	0.3 g	0.3 g	0.5 g	0.5–1.0 g
The sea – Area B	0.3 g	0.3 g	0.7 g	0.3–1.0 g
The sea – Area C	0.4 g	0.4 g	0.8 g	0.2–1.0 g

* At sea, the lower value applies to situations where longitudinal accelerations are at work – when the ship is rolling lengthways, the pressure exerted by the cargo on the floor temporarily decreases.

** The figures in brackets refer to short-duration pulses lasting up to 150 ms.

Source: CTU Code, Chapter 5.

Four practical conclusions can be drawn from the table:

1. The strongest forward thrust usually occurs on the road, rather than at sea. A braking lorry generates 0.8 g – twice as much as a ship on the open sea in a longitudinal direction.
2. Transverse motion predominates at sea. A ship’s roll on the open sea can reach up to 0.8 g from side to side.
3. At sea, the load ‘slides’. As the pressure on the floor decreases, so does the friction. A load that remains firmly in place on the floor whilst driving may start to slide when on a wave.
4. The safety measures are designed to cope with the worst-case scenario along the entire route, separately for each direction. The container does not know whether it is currently being transported by lorry or sailing across the Bay of Biscay.

The table shows the force scale, but this alone is not sufficient to design a lashing system. The selection of securing measures requires an analysis of the specific load: its mass, dimensions, centre of gravity, method of support and route.

Maritime areas – how to assign a route to them

The CTU Code classifies bodies of water according to what is known as the significant wave height (Hs), which is the average of the highest one-third of the waves, statistically exceeded once every 20 years:

• Area A (Hs ≤ 8 m): the Baltic Sea including the Kattegat, the Mediterranean Sea, the Black Sea, the Red Sea and the Persian Gulf.
• Area B (Hs from 8 to 12 m): The North Sea, the Skagerrak, the English Channel, the Sea of Japan, the Sea of Okhotsk, and coastal and inter-island voyages in the central parts of the Atlantic, Indian and Pacific Oceans.
• Area C (Hs > 12 m): other bodies of water, including the open ocean.

A route’s classification is determined by its most difficult section. In practice, this means that almost every sea consignment from Poland outside the Baltic and North Sea regions passes through Area C – even a voyage to the Mediterranean passes through the Bay of Biscay and the Atlantic.

Rules for securing cargo in a container

The CTU Code does not prescribe a single security method. It sets out principles which – when combined with knowledge of the specific cargo – enable the appropriate solution to be selected.

Friction helps, but it is not enough on its own

Friction between the load and the container floor absorbs some of the forces, but its magnitude depends on the materials (wood, steel, plywood flooring), their condition (moisture, dirt) and the pressure applied. And the pressure – as shown in the acceleration table – temporarily decreases at sea. Anti-slip mats significantly increase friction and are one of the cheapest ways to reduce the forces that the other securing measures have to absorb. However, they are no substitute for lashing or tie-downs.

For the same reason, the CTU Code advises against the use of lashing straps across the top of the load (pressing it down onto the floor) as the primary means of securing it against movement – unless the load is of low mass. With heavy machinery, such lashing straps are far less effective than their number might suggest.

Blocking and filling empty spaces

The most effective method of securing a load is one in which the load has nowhere to shift. In accordance with guidelines based on the CTU Code, the total amount of free space in any horizontal direction should not exceed 15 cm. Larger gaps should be filled or blocked:

• stowage timber – wedges, struts, locking beams and joists, made from IPPC-certified stowage timber;
• stowage bags (air cushions) – for filling the spaces between cargo units, selected to suit the width of the hold and the weight of the cargo;
• locking mechanisms based on the container’s load-bearing elements, with the load distributed over a larger surface area.

The side walls and doors of the container have limited strength. Heavy loads should not rest on them at any single point – the force must be distributed or transferred to the locking mechanisms.

Tie-downs and container securing points

The lashing points inside the container are not as strong as many people assume. According to the CTU Code (section 6.2.5), the floor fittings in a container have a minimum safe working load (MSL) of at least 10 kN in any direction – in newer containers, this is often 20 kN. The points at the upper side beams have a minimum capacity of 5 kN. For a machine weighing several tonnes, this is not much; therefore, when handling heavy loads, the force should be distributed across multiple points, lashing straps with locking mechanisms should be used, or a different type of unit should be selected. Flat-rack platforms have lashing points with an MSL of at least 30 kN, and often 50 kN.

Woven polyester straps with buckles are most commonly used for lashing. They withstand vibrations well and do not damage the surface of the load, provided that the edges are protected with corner protectors.

Weight distribution and load support

Heavy items should be placed at the bottom, and the centre of gravity of the entire load should be as close as possible to the centre of the container’s length and width. Concentrated loads, such as machine feet or narrow skids, must be distributed across the floor beams so as not to exceed the permissible floor pressure. The total mass must not exceed the container’s load capacity as stated on the CSC plate.

Tall and narrow loads

A load whose height is large in relation to the width of its base may tip over before it has a chance to shift. The risk is greatest in the transverse direction on the open ocean. Such cargoes require securing at the top, not just at the base. For custom-made transport crates, the position of the centre of gravity is marked on the outside of the packaging so that the stowage officer knows what they are dealing with.

The same machine, three routes

Let’s take a single machine weighing several tonnes, packed in a crate on skids and shipped in a 40-foot container. The cargo is the same, the container is the same – yet the securing plan is different for each of the three routes.

Route 1: Gdynia – Helsinki (Baltic Sea, Area A). A short voyage across calm waters. The greatest forces are encountered not at sea, but on the road: during delivery to the port and collection from the consignee, the cargo must withstand 0.8 g during braking. On the Baltic Sea, lateral forces reach 0.5 g. The emphasis is on secure longitudinal securing and stable support. Protection against moisture is simpler, as the cargo spends several days in the container.

Route 2: Gdańsk – Houston (Atlantic, area C). The ship passes through the Baltic Sea (A), the North Sea and the English Channel (B), and then across the open Atlantic (C). Lateral forces rise to 0.8 g, whilst during longitudinal rolling, the pressure on the floor drops to as low as 0.2 g – friction is no longer an ally. Transhipment often takes place at a transhipment port. Several weeks in a container, passage through various climate zones and the risk of condensation require anti-corrosion protection, as described in our article on protecting machinery for maritime transport. The emphasis is on lateral protection and preventing the machine from tipping over.

Route 3: Poland – China by rail. Lateral forces in rail transport amount to 0.5 g, but short-lived impacts during the coupling and manoeuvring of trains can reach 1.0 g. The track gauge changes twice along the route (from 1,435 mm to 1,520 mm and back again), so the container is transhipped between wagons. The journey takes several weeks, with significant temperature fluctuations. Emphasis is placed on longitudinal locking and fastenings that do not come loose under the influence of repeated impacts and vibrations.

Route	The prevailing direction of forces	Additional risks	What to focus on
Gdynia – Helsinki	Longitudinal (road sections)	Port handling operations	Forward and backward locking, support
Gdańsk – Houston	Transverse (ocean)	Reduction in floor pressure, condensation, transhipment at a transhipment port	Side protection, roll-over protection, anti-corrosion protection
Poland – China by rail	Longitudinal (impact)	Overloads when changing track gauge, vibrations, temperature fluctuations	Longitudinal locking, fastenings resistant to loosening

The same crate and the same container – three different securing methods. That is why a reliable quotation for container stowage always begins with a question about the full route. We discuss in more detail how the mode of transport affects the cost of securing cargo in our article ‘Sea and land transport from a packaging perspective’.

Stowage plan – what information to prepare before placing an order

The stowage plan specifies where each item of cargo will be located within the transport unit, what it will rest on, and how it will be secured in every direction. Its quality depends directly on the information the contractor receives from the consignor. The more accurate the information at the outset, the less improvisation is required on the loading bay.

Cargo details

1. The gross weight of each unit of cargo – including packaging, preferably from a weighing record rather than a catalogue.
2. Overall dimensions – and a drawing or photographs if the shape is irregular.
3. The position of the centre of gravity – particularly where it is offset from the geometric centre. This should be indicated on the packaging.
4. Methods of support – skids, frame, pallet, machine feet – and the points at which the load may be supported.
5. Points where loads may be attached – carrying handles, lugs – and components that must not be subjected to loads or pressure.
6. Cargo sensitivity – to shocks, tilt, moisture and pressure. If the recipient requires shock or tilt indicators, it is worth specifying this straight away.
7. Stackability – whether anything can be placed on top of the load.
8. Dangerous goods – UN class and number, where applicable. The packaging of such cargo is also subject to the IMDG regulations.

Transport data

1. Full route – place of loading, ports, transhipments, road and rail sections, country of destination.
2. Container type – 20', 40', 40' High Cube, open-top, flat rack – or a request for the appropriate type to be selected.
3. Location and date of stowage – and whether a forklift or crane is available on site.
4. Unloading conditions at the consignee’s premises – what equipment will be used to unload the container.
5. Requirements set out in a contract, letter of credit or insurance policy – e.g. a mandatory inspection, a photographic report, specific labelling.

What you should receive after stowage

• layout plan for the cargo in the container,
• a description of the security measures used,
• photographic documentation of the successive stages, including just before the door is closed,
• seal number and the information required to submit a VGM declaration,
• on request – a report on the loading inspection carried out by an independent SGS inspector.

This documentation is not just a formality. In the event of damage, it serves as key evidence that the cargo was secured in accordance with best practice for securing cargo.

Why can’t a fastening be designed ‘by eye’?

The forces acting in each direction vary and change depending on the section of the route. Friction depends on the materials and the instantaneous pressure. The container’s lashing points have a limited load-bearing capacity, and a load with a high centre of gravity may tip over before it shifts. Each of these factors must be assessed for a specific load. A few straps tightened ‘just in case’ provide a sense of security, but do not guarantee that the load will arrive at its destination intact.

Checklist before closing the container door

1. The container has a valid CSC plate showing the date of the next inspection; it is watertight, dry and clean.
2. There are no traces of previous loads or visible pests inside.
3. The timber used for stowage and packaging is ISPM 15-certified (IPPC certificate).
4. The cargo was arranged as planned: heavy items at the bottom, with the centre of gravity as close to the centre of the container as possible.
5. The gaps have been filled – the total width of the gaps in each horizontal direction does not exceed 15 cm.
6. The lashing straps are taut, the edges are protected by corner protectors, and the load does not rest on any single point against the walls or doors.
7. Photographic documentation was carried out, including just before closure.
8. A seal complying with ISO 17712 was affixed, its number was recorded and the VGM was provided.

If you’d like to know what mistakes most commonly occur during the machine packaging stage, take a look at the article on the most common mistakes made when packaging machines for export.

Container stowage at Danpol

Danpol specialises in the loading and stowage of all types of sea containers – from standard 20’ and 40’ containers, through to High Cube containers and flat rack platforms. We operate throughout Poland. We use only approved materials to secure cargo: IPPC-certified dunnage timber, Cordstrap woven straps, dunnage bags and anti-slip mats. Our team has undergone training provided by SGS Polska and Cordstrap. At the customer’s request, we can arrange for an audit to be carried out by a licensed loading inspector.

We integrate stowage with the other stages of shipment preparation – export packaging, the manufacture of bespoke crates and anti-corrosion protection – ensuring that the packaging and securing within the container are designed as a single process, rather than separately. You can find examples of our work in the posts ‘Stowage of a container for sea transport’ and ‘Stowage of machinery in a container’.

FAQ

Is the CTU Code compulsory in Poland?

It is not a legal instrument, but a code of good practice drawn up by the IMO, the ILO and the UNECE. In practice, however, it serves as a benchmark for assessing whether cargo has been secured with due care – for insurers, surveyors and the courts. Certain requirements associated with the code are, however, mandatory, such as the VGM declaration under the SOLAS Convention or the IMDG Code provisions for dangerous goods.

Who is liable if the cargo shifts inside the container?

In the case of an FCL container packed and sealed by the consignor – usually the party that packed and dispatched it. The Maritime Code exempts the carrier from liability for damage resulting from inadequate packaging and from the shipper’s actions, whilst standard cargo insurance clauses exclude damage caused by poor packaging, which also includes stowage within the container.

What acceleration values are used in maritime transport?

The CTU Code divides bodies of water into three zones. Lateral forces: 0.5 g in Zone A (e.g. the Baltic Sea), 0.7 g in Zone B (e.g. the North Sea) and 0.8 g in Zone C (the open ocean). Longitudinally: 0.3–0.4 g. Added to this are forces from road and rail sections – the safety margin is designed for the highest values along the entire route.

Are anti-slip mats sufficient to secure the load?

No. Mats significantly increase friction and reduce the forces that other securing devices have to bear, but at sea, the load pressure on the deck decreases temporarily, and with it, the friction. Mats are used in conjunction with lashing and tie-downs, not instead of them.

Does the shipowner check that the cargo is secured in an FCL container?

Generally speaking, no. The shipowner accepts the sealed container and is responsible for securing it on board the vessel, but not for the stowage of the cargo inside it. The bill of lading usually includes a ‘shipper’s load, stow and count’ clause, which confirms that the shipper is responsible for the contents and their securing.

How does stowage differ from securing a load?

Stowage is a comprehensive process: planning the arrangement of the cargo within the transport unit, supporting it, filling any gaps and securing it. Cargo securing is one element of this process – lashing, locking mechanisms and other measures that immobilise the goods.

Summary

The CTU Code is not a regulation, but in the event of damage, it is used to assess whether a container has been packed correctly. The Code requires cargo to be secured against the highest accelerations encountered throughout the entire journey – ranging from 0.8 g during a lorry’s braking manoeuvre to 0.8 g laterally on the open ocean – and clearly assigns responsibility for the interior of the container to the party that packs and dispatches it. Transport regulations and cargo insurance terms and conditions lead to the same conclusion: the consequences of poor stowage are borne by the consignor. It is therefore advisable to start with reliable data on the cargo and the route, and to entrust the work to a contractor who will prepare a stowage plan and document its implementation.

Are you planning to ship by container? Contact Danpol – provide us with details of your cargo and route, and we’ll prepare a quote for container stowage, including securing the cargo and the necessary documentation.