Transportation & Logistics Analysis

Good practice when transporting dangerous goods by ship

November 26 2021

Transporting dangerous goods by sea in containers is governed by very precise regulations. This article aims to recall good practice in this field and the main traps to avoid, without going into the details of the regulations.

The day-to-day handling of dangerous goods is regulated by the International Maritime Organisation's International Maritime Dangerous Goods (IMDG) code and the MARPOL Convention. The code is updated annually and those involved in international trade involving these kinds of goods need to be given training, as well as periodical refresher courses.  

My purpose today is not go into the detail of the regulations but rather to pass on a few tips to enable the transportation of dangerous goods to be better understood, given that incidents involving goods of this type can have tragic consequences, as was sadly shown by the fire which broke out aboard the Maersk Honam in 2018.

Good to know

  • Watch out for regulatory differences according to transport mode

The ADR agreement, which covers the transportation of dangerous goods by road, provides for the notion of limited quantities, which is not the case for the IMDG. If a full container load contains 1 kg of dangerous goods, the whole container is deemed to be dangerous. A full container can, therefore, be considered non-dangerous on the inland leg of its journey and then dangerous on the maritime leg. It is not very logical but that is the way it is.

So long as the dangerous goods declaration has not been accepted by the shipping company, no reservation can be considered to have been made.  

  • Make precise declarations

The goods must be declared not under their commercial name but under the UN code attributed to them in the IMDG code. If this is not done, they risk not being accepted for reservation. Their flashpoint, which is to say the critical temperature at which their state is modified, needs to be stated precisely and must always figure in the document.

The most common case is class 3, which covers inflammable liquids with a flashpoint of less than 60°C. This class, which covers about 70% of all dangerous goods transported by container, poses less problems than the other categories of dangerous goods (see the summary of classes below) and, most of the time, is accepted virtually automatically.

Be careful, though! It is not because class 3 goods are generally accepted fairly easily that they are not subject to particular routing conditions, which, in some cases, can greatly complicate and even make impossible certain export operations. Such is the case for goods which need to be transhipped in Singapore, which are subject to specific regulations (PSA 1/2/3). Since the tragic explosion in the port of Tianjin in 2015, moreover, some Chinese ports have reinforced their rules concerning the handing of dangerous goods or even banned them altogether. It is best to check the situation before embarking on any operation, therefore.

  • Prepare shipments well in advance

Reservations for dangerous goods should never be made at the last minute, particularly now ! The process of approval or refusal by the shipping company can take several weeks, since the shipping companies loading aboard any given ship need to discuss in real time whether or not to accept dangerous goods. If quotas for certain classes of dangerous goods aboard the ship have been reached, new bookings will be refused.

Port call cancellations and last-minute route changes of the kind that have become so common today can result in the original reservation being cancelled. In addition, if the container is already on the quayside, the sender has to remove it at his own cost. This kind of incident is becoming increasingly common at the moment when shipping service timetables are suffering from widespread disruption.

  • Respect deadlines scrupulously

Shipments need to be organised so as to ensure that good do not spend more than 24-48 hours on the quayside before they are loaded. This is general practice at all the world's major terminals and is intended to preserve security and limit risks in the areas reserved for dangerous goods. The upside of this requirement is that, like reefers, dangerous goods are always given priority for loading. The risk of them being left on the quayside - "rolled over" - is, therefore, very low.  

NB: My shipping company wants me to sign a "jettison letter". What is it?

It is a letter from the shipper authorising the shipping company to get rid of the shipment if the ship finds itself in danger. It is for this reason that the most dangerous goods are generally loaded sideways on at the highest point on the deck. This made sense when ships were equipped with their own loading gear but makes less sense today when the giant container ships have only very limited capacity to jettison a container which poses a threat.  

A summary of classes and their acceptability

  • Class 1 : Explosives

These are always refused with just a few exceptions, which require particular handling procedures and authorisations. These include fireworks, 1.4S class hunting cartridges, airbag detonators and some explosives used for construction work. All explosive materials of a military nature are excluded from the commercial shipping operations dealt with in this article, although this does not mean that they are never carried by regular line vessels.

  • Classe 2 : Flammable gases

These are accepted on a case-by-case basis, but not by all companies or on all lines. Examples of goods in this category are disposable lighters and aerosols.

  • Class 3: Flammable liquids with a flashpoint of less than 60°C

This is the most common class and the one which, normally speaking, poses the least problems. All companies generally accept goods in this class although routings between Europe and Asia are becoming more complicated, to the point where some export operations are now under threat because they have become more complicated and costly to organise. Oil products, lubricants and additives are examples of goods in this category. 

  • Class 4 : Inflammable solids

These are generally accepted but are subject to tighter restrictions than goods in class 3. Some class 4 products are particularly unstable. Such is the case for nitrocellulose, which needs a high hygrometry level to stay stable. My professional memory is still marked by the story of a container which stayed on the quayside in Dubai for six months because of a failure on the part of the receiving party. No one wanted to go near it and the terminal had to be cleared in epic fashion.

  • Class 5: Oxidising substances and organic peroxides

These products are very rarely accepted except under very strict conditions and in limited quantities. This category includes ammonitrates like fertilisers and organic peroxides, which are particularly unstable and potentially highly dangerous. It was this kind of product which was involved in the explosion which ravaged the port of Beirut in August 2020.

  • Class 6: Toxic and infectious substances

These goods can be transported relatively easily. They are accepted by the great majority of shipping companies even if they require stricter conditions than goods in class 3.

  • Class 7: Radioactive material

These do not come into the field of normal commercial operations. They have to go through particular acceptance procedures, need to respect precise handling requirements and are subject to very specific checks carried out under the authority of the states concerned.

  • Class 8 : Corrosive products

They can be transported fairly easily like those in class 6.  

  • Class 9: Miscellaneous dangerous substances and articles considered to be slightly dangerous

These products are generally accepted fairly easily, a little like those in class 3. They can nevertheless bring new forms of major risk. This is particularly true for lithium batteries, which are in high demand for "green" mobility. A video, which went viral in early 2020, shows the race to unload a blazing container containing lithium batteries, raising questions about the "slightly dangerous" label attached to goods of this kind, which are subject to changing legislative requirements.

Two golden rules

By way of a quick conclusion, I would insist on two golden rules:

  • Respect training requirements scrupulously
  • Never cheat by not declaring goods or not declaring them accurately.

It is not worth the risk, since your insurance policy will not cover you if you endanger a ship, its cargo or its crew, without even taking account of the potentially catastrophic environmental damage that can result from a wrong declaration.

Personally, I think that the recent rise in casualties, coupled with a balance of power which currently favours the shipping companies, is making dangerous goods increasingly unacceptable all over the world. For some shippers, this can mean having to rethink their global production and distribution logistic networks. A production plant cannot be relocated with a simple click of the fingers, particularly not where dangerous goods are concerned. These changing transport conditions need, therefore, to be taken into account when planning for the years ahead.

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Expert in Ocean shipping for 25 years, Jerome puts all his knowledge of the industry to contribution for Upply. Ship captain at heart, he has written the English-French Lexicon of Containerized Shipping (Paris: CELSE, 2001).
See all its articles