Container weight FAQs

Since 1 July 2016, all shipping containers for export from New Zealand require a verified weight (Verified Gross Mass or VGM) before they can be loaded on a ship. The shipper is responsible for providing the VGM. The container must not be loaded if it doesn’t have a VGM.

The VGM is a requirement of the International Convention for the Safety of Life at Sea (SOLAS) and is given effect in New Zealand law in Maritime Rules Part 24B: Carriage of Cargoes – Stowage and Securing.


Who is this information for?

All parties in the transport chain need to be aware of the VGM requirements, and be sure that they understand their individual responsibilities. These parties include:

  • Shippers - any person or organisation that offers goods for carriage by sea, and includes any person who arranges carriage on behalf of another person.
  • Packers and consolidators – organisations that pack shipping containers and consolidate consignments from individual shippers into containers.
  • Carriers and carters – organisations that physically carry the containers from the shipper or packer/consolidator to the container terminal (port and inland terminals).
  • Freight forwarders or forwarding agents – organisations that arrange for the transport of goods from the shipper to the final destination – sometimes known as non-vessel operating common carriers (NVOCCs).
  • Container terminal operators and port operators.
  • Shipping lines.

The responsibilities of each party in the transport chain depend on the nature of the commercial arrangements that the shipper has with them. In the questions below, we have used the general term ‘freight company’ to refer to packers, carriers, freight forwarders, and other parties who have a role in delivering the shipper’s goods to the port or container terminal for export.


Requirement to have a Verified Gross Mass

Q. Why do I need to verify the weight of my container?

This is all about safety of ships and seafarers. Misdeclared weights make it difficult to plan the safe stowage of cargo on a ship. This can result in the collapse of container stacks, overstressing of the ship’s structure, or instability of the ship itself.

Under the international SOLAS (Safety of Life at Sea) Convention there is already a requirement for shippers to declare the gross mass of cargo to be shipped.

Since July 1, 2016, the declared gross mass for all containers shipped internationally must be confirmed as accurate and signed off by the shipper. There will be an obligation on the Master of a ship not to load any container that doesn’t have a verified gross mass.

Signed declarations by shippers are already required for consignments of dangerous goods to be carried by sea so that they can be correctly and safely stowed on a ship. This is a similar system for ensuring that containers loaded onto a ship have a known and reliable weight for the same purpose.

Q. Who is the shipper?

The shipper means any person who offers goods for carriage by sea, and includes any person who arranges carriage on behalf of another person. Whether or not you are the shipper will depend on the nature of the commercial contract you enter into with any freight company or other party to carry your goods to your customer. They should tell you whether you need to provide a VGM for your consignment.

Q. What is a Verified Gross Mass and how do I measure it?

The VGM is the combined weight of the container and its contents. There are two ways of determining this.

Method One requires the packed container to be weighed using calibrated and certified weighing equipment.

Method Two requires the contents of the container to be weighed (including packing material and dunnage) and added to the tare weight (empty weight) of the container, using a method acceptable to the Director of Maritime NZ.

Q. My container is going from Auckland to Christchurch by road or rail and by ferry across Cook Strait. Does it need a VGM?

NO. The rule only applies to containers carried on an international voyage, and doesn’t apply to containers carried on rail wagons or road vehicles aboard a roll-on, roll-off (RORO) ship to another New Zealand destination.

However, if the container is being transhipped to another New Zealand port for export, then it will require a VGM before it can be loaded onto another ship at that port. The freight company will not be able to present your container at a port for export without a VGM, so they may require you to provide a VGM before they will accept the container for domestic shipment. You should confirm this with your freight company.

Q. My container is going by ship from Auckland to Christchurch. Does it need a Verified Gross Mass?

The maritime rule only applies to containers carried on an international voyage. Domestic shipping lines may choose to require a VGM as well, but that is for them to decide.

However New Zealand port companies are requiring a VGM for any container shipped through their terminals, irrespective of whether the container is being loaded for a domestic or international voyage. You should check with the shipping line or your freight company to confirm their requirements.

Q. How do I know what ship or voyage my container is being carried on? I’ve just booked it through the freight company.

The freight company shipping the container on your behalf will be able to tell you, so that you can provide the VGM if required, or you will need to make sure they provide it for you.

Q. My container is being carried on a domestic feeder service from Nelson to Auckland before it goes to Singapore. Does it need a Verified Gross Mass before it gets loaded in Nelson? And what will happen if it doesn’t have one?

If it doesn’t have a VGM it may not be accepted for loading in Nelson. You should check with the domestic shipping operator or your freight company to confirm their requirements (see above).

Q. My consignment is being consolidated with other freight by a packer at another location. I can’t provide a Verified Gross Mass for the container because I’m not packing it. What do I need to do?

The organisation responsible for final packing of the container – ‘the last person to close the door’ – is generally responsible for determining the VGM. They may arrange for the container to be weighed once it is packed. Alternatively, if they are using Method 2 (adding the weight of the container and all its contents to get a VGM) they may require you to provide the VGM for your consignment so they can then calculate the final loaded figure. They should advise how this information is to be provided and in what form. You should contact the packer/consolidator.

Q. My container was loaded in New Zealand before 1 July but will be transhipped at an overseas port after 1 July. Will transhipment be held up if it doesn’t have a VGM?

The IMO has agreed that Maritime Administrations internationally should take a practical and pragmatic approach in the first three months after 1 July to allow containers loaded before 1 July to be transhipped to their final destination without a VGM.

Advice regarding verification of gross mass of packed containers [IMO website] IMO Maritime Safety Committee circular MSC.1/Circ. 1548 [PDF: 39kB, 1 page]

Q. Do the new rules apply to imported containers?

NO. The New Zealand rules only apply to containers exported from New Zealand. As the requirement is an international one, each country that is party to the SOLAS Convention will have its own legislation requiring a VGM. If a problem regarding a declared VGM is identified in a container landed in New Zealand, then Maritime NZ can take the matter up with both the flag State of the ship, and the State where the cargo was loaded. A similar process would be followed to that used for misdeclaration of dangerous goods in an imported container.

Q. Do the new rules apply to empty containers?

NO. The rules only apply where cargo is carried in a container, so an empty container for export does not require a VGM. However, you should contact your freight company or shipping line to confirm their requirements.


Determining the Verified Gross Mass

Q. If I used Method One (weighing the packed container) what do you mean by “calibrated and certified equipment”?

Calibrated and certified equipment is a trade approved weighing instrument (an instrument approved in accordance with the Weights and Measures Act 1987, and Weights and Measures Regulations 1999).

Using New Zealand’s Weights and Measures System for SOLAS [PDF: 34kB, 3 pages]

Q. What is the standard of accuracy required for Method One?

Trade approved equipment used to determine a VGM must comply with legal tolerances and must have a current certificate of accuracy (see Weights and Measures Act and Regulations). Weighing instruments approved as Class III or IIII must have a scale interval no greater than 50kg. Weighing instruments approved as Class Y(b) must have a scale interval no greater than 100kg. Scale intervals for other classes of instruments will be considered on a case-by-case basis.

Q. Who can issue a ‘Certificate of Accuracy’ on trade approved equipment?

Accredited Persons, who are authorised under the Weights and Measures Act to examine and test trade approved equipment, can issue a ‘certificate of accuracy’. A list of Accredited Persons is available on the Trading Standards website.

Q. Will ports have weighing instruments that can be used to weigh my container?

Ports have indicated that in general they will not be providing container weighing services, but have provided some information on weighing services available elsewhere. (see below). Your container will need to have a VGM before it arrives at the port, otherwise it is likely they will not accept it into the terminal. Your freight company or packer should advise you on what is required.

Q. If I’m using Method Two to determine the Verified Gross Mass of my container, where do I get the tare weight (mass) of the container and how do I know the figure is reliable?

The tare weight will be marked on the container. The owner of the container is responsible for ensuring that the tare weight is marked and it is accurate. In addition, the Maximum Operating Gross Mass is required to be stamped on the CSC approval plate on the container, and in any case the VGM must not exceed the Maximum Gross Operating Mass.

Q. I wish to use Method Two. However our product is sold by volume, not mass. Can I use a conversion from a measured volume, to calculate the mass of my product and will the shipping line accept this for the purposes of determining a Verified Gross Mass?

Method Two allows alternative procedures to be used to establish a VGM that are acceptable to the Director. This provides shippers with a degree of flexibility to account for different cargoes that are not commonly shipped on a weight basis, such as pulp, lumber and produce. Such procedures must provide an accurate and reliable VGM (comparable to that achieved with Method One).

The procedures should be based on methods of known accuracy supported by a quality control system to ensure a consistent process and verifiable weights. For example, the use of conversion factors for volume to mass would be acceptable, provided that the process for establishing and verifying those factors on an ongoing basis is subject to a rigorous process. This includes sampling and weighing, using calibrated and certified equipment. The onus remains on the shipper to demonstrate that their process can produce a reliable and accurate VGM.

Guidance is provided in the Advisory Circular on what are considered to be acceptable methods for determining the VGM using Method Two (see previous question).

Part 24B rules page

Q. Is Maritime New Zealand going to approve shippers using Method Two?

NO. We are not planning to run a formal approval system for shippers using Method Two.

Guidance will be provided on what are considered to be acceptable methods for determining the VGM using Method Two.

Q. What is the tolerance on the VGM?

There is no tolerance specified in the rule. The requirement to use trade approved equipment means that the VGM should have an accuracy as specified in the Weights and Measures Act 1987 and supporting Regulations.


Notification of Verified Gross Mass

Q. Are you going to specify which documents the Verified Gross Mass should be provided on?

Shippers are required to state the VGM in the shipping documents, which may be transmitted by electronic means. The rule does not specify the format or location of the VGM, except that it must be provided on the shipping documents, clearly state that it is the VGM, and be signed by the person authorised to do so by the shipper.

There has been no change to the regulation in this respect. Currently SOLAS requires that the correct weight be provided in the shipping documents. What is considered a shipping document has not changed.

Q. Are you going to specify a format for the VGM?

There are various forms of shipping documentation in circulation, and - in the absence of an international pro forma requirement - it would be impractical for Maritime New Zealand to specify a format for the documentation of the VGM.

Q. Who can sign the Verified Gross Mass declaration?

The VGM declaration must be signed by a person duly authorised to do so by the shipper. In light of the varying sizes, types, and structures of shippers throughout New Zealand it is not considered practical to specify who in an organisation should be signing the shipping documentation. It is up to the shipper to make this decision and provide the appropriate person or people with the authority to do so.

Q. Are you going to specify a time by which the VGM must be provided?

NO. The rule requires the VGM to be provided to the port sufficiently in advance of loading to ensure proper loading and stowage of the cargo. New Zealand ports and shipping companies all have operating procedures and requirements around the provision of cargo documentation. In light of the individual conditions and procedures under which ports, shipping companies, shippers, packers, freight forwarders and carriers operate, it is not practicable for the rules to specify a minimum time.

Ports and shipping lines will determine the cut-off time for receipt of VGM documentation to allow them to plan the loading and stowage of the ship, and will advise their customers accordingly.

Q. What will happen if a VGM is not provided?

There is a clear requirement in the rule that if a shipping document doesn’t have a VGM, or the Master or the terminal representative does not have the VGM information, then the container must not be loaded on to the ship. There is also an obligation on the Master not to accept cargo on board if he or she is not satisfied it can be transported safely. In short, a container without a VGM won’t be loaded.

Ports companies have set out their requirements for receipt of VGM information and what actions they will take if a container is presented without a VGM. The economic consequences of a failure to provide a VGM are a commercial matter for the parties involved.

Preparing for VGM [Website: Port of Napier]



Q. How will Maritime New Zealand be enforcing the new rules? Will you be doing spot checks on container weights?

There will be an element of self-enforcement in the system in that ports and shipping lines will not be accepting export containers for loading that do not have a VGM.

Maritime NZ does not currently plan to do on-the-spot checks or random weighing of containers, nor are most other maritime administrations globally intending to do this. However, this does not mean there will be no enforcement. We will be monitoring the implementation of the new rules, which may include audits of shippers to check their systems for determining the VGM.

In addition, where concerns about grossly inaccurate weights are brought to our attention, or there is evidence of consistent misdeclaration or no VGM, we will follow this up with the shipper.

Where the lack of a verified weight or an obviously incorrect weight becomes a safety issue, or there were serious breaches of the verified weight obligations, Maritime NZ would be notified as appropriate. The action taken by Maritime NZ upon notification will depend upon the nature of the breach.

Maritime NZ will take a practical and pragmatic approach to enforcement in the first three months from 1 July to allow all parties in the transport chain to refine their processes for documenting, communicating and sharing VGM information.

This approach has been agreed by members of the IMO and is consistent with Maritime NZ’s own compliance operating model which supports those making best efforts to comply with the new requirements.

This does not excuse any party from the requirement to determine the VGM for all containers to be exported from 1 July and to make all endeavours to transmit the VGM and authorising signature to the terminal representative and ships Master.

Q. What are the penalties for non-compliance?

There are penalties under the Maritime Transport Act for actions in respect of a ship which causes unnecessary danger or risk to persons or property. There are also penalties for providing information relating to the safety of a ship that is known to be false, or in a manner that is reckless as to whether it is false.

Q. What if the trade approved equipment is found to be non-compliant?

Trading Standards regulates trade approved equipment and is responsible for the enforcement of this area. See the Trading Standards website for more information.

Q. How does this new requirement relate to weight requirements for transport by land and the enforcement work done by the Police Commercial Vehicle Inspection Unit?

Land transport rules focus on axle weights and ensuring a vehicle does not exceed its safe load. This is what the Police check in their inspections, as well as other vehicle safety matters. The actual weight of the container is not directly of interest, provided that the maximum limits in the land transport rules are not exceeded. A VGM for a container may be useful for demonstrating compliance with land transport rules, but compliance with weight requirements on the road does not mean compliance with VGM requirements for carriage by sea.


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