Transport of hay, haylage and silage on ships

The recent drought in Sweden has led to a shortage of forage (hay, haylage and silage). Concerned animal owners, mostly horse owners, therefore seek to import forage from other countries. If transported on road or railroad this goods does not need to be classified as dangerous, but if forage is transported on ships the provisions of the IMDG Code become applicable. The Swedish Transport Agency wants to clarify what applies to the transport of forage on ships.

Transport of packed dangerous goods is regulated in the IMDG Code. It states that hay and straw may constitute dangerous goods (UN 1327 HAY, STRAW or BHUSA). These products are considered flammable solids, belonging to class 4.1. In some cases there is also a risk of spontaneous combustion. Some of the provisions of the IMDG Code, such as the prohibition against transport of hay that is wet or contaminated by oil, show that also this risk has been taken into account in the provisions regarding hay, straw and bhusa.

The shipper of the goods is responsible for the classification and must determine whether the goods carry risks that require them to be assigned to a class of dangerous goods. When it comes to hay, straw and bhusa, the focus for the classification is the risk of the goods being readily combustible, in the sense that it can be easily ignited by brief contact with an ignition source, such as a burning match, and if the flame spreads rapidly. In such a case, the goods shall be classified as dangerous and the provisions of the IMDG Code regarding UN 1327 HAY; STRAW or BHUSA be applied.

The requirements according to the IMDG Code

  • The provisions of the Code shall not apply to hay with a moisture content of less than 14 percent if:
    • The hay is compressed in bales
    • There is a certificate from the shipper stating that the product does not present any class 4.1, UN 1327, hazard in transport and that its moisture content is less than 14 percent
    • The bales are shipped in a closed cargo transport unit, meaning a cargo transport unit which totally encloses the contents by permanent structures with complete and rigid surfaces. Cargo transport units with fabric sides or tops are not considered closed cargo transport units.
  • Hay with a moisture content of 14 percent or more (or drier hay which cannot be exempted under the conditions described above) shall be transported in accordance with the provisions of the IMDG Code. The same applies for straw and bhusa, regardless of moisture content. In these cases a dangerous goods declaration (DGD) needs to be completed and the bales need to be marked as belonging to class 4.1 (the bales are exempt from class marking if loaded into a cargo transport unit which displays any relevant labels, placards and marks in accordance with chapter 5.3 of the Code). There is no requirement for closed cargo transport units to be used, but the provisions for stowage and handling require the bales to be properly covered with tarpaulins or the like when stowed on board the ship.*
  • Haylage: The IMDG Code does not distinguish between different types of forage that may be available on the forage market. All types of forage that are to be transported on a ship must therefore be classified by the shipper according to the hazards presented by that particular product, to determine whether or not it needs to be declared as dangerous goods belonging to class 4.1, UN 1327 HAY, STRAW or BHUSA.
  • Transport of loose hay or hay, straw or bhusa that has become wet or contaminated with oil is prohibited.


It is the understanding of the Swedish Transport Agency that silage, due to its moisture content (normally around 45-60 percent) is not flammable. It may therefore be transported as regular goods, i.e. without being classified as dangerous goods. The prohibition against transport of wet hay, straw or bhusa in SP 281 should be interpreted only as a prohibition against transport of such products after they have been rehydrated, since this creates conditions where the risk of spontaneous combustion is greatly increased.

The responsibility of the master

The master of the ship is always entitled to decide what is loaded onto the ship or not. A consignment may therefore be rejected for transport although the provisions of the IMDG Code have been correctly applied.

* 7.1.5. of the IMDG Code


"Unless carried in closed cargo transport units, bales shall be properly covered by tarpaulins or the like. Cargo spaces shall be clean, dry and free from oil or grease. Ventilator cowls leading into the cargo space shall have sparking-preventing screens. All other openings, entrances and hatches leading to the cargo space shall be securely closed. During temporary interruption of loading, when the hatch remains uncovered, a fire-watch shall be kept. During loading or discharge, smoking in the vicinity shall be prohibited and fire-fighting appliances kept ready for immediate operation."