Shipping & logistics

ISO tank (tank container)

A reusable tank of about 20,000–26,000 litres, usually stainless steel, set in a steel frame with 20-foot container dimensions. It is suitable for chemicals, solvents, dangerous goods classed under the IMDG Code and food-grade liquids, with options for heating jackets, pressure rating and insulation. A cleaning certificate (ECD) is required before each loading, and previous cargoes (usually the last three) are checked for compatibility.

Related terms

Flexitank

A single-use, multi-layer polyethylene bag fitted inside a standard 20-foot dry container, carrying 16,000–24,000 litres of non-hazardous liquid. For vegetable oils, glycerine, base oils, latex, wine, syrups and some non-food chemicals it is far cheaper per litre than drums or IBCs. Dangerous goods cannot be carried; for food cargo check the bag’s food-grade certificate and the container’s cleanliness.

Container types (20’, 40’, 40’HC, reefer, open top)

A 20-foot container (about 33 m³, payload around 25–28 t) suits heavy, dense cargo such as metals, minerals and bagged chemicals; a 40-foot (67 m³) and 40-foot high cube (40’HC, 76 m³, ~26 t) suit light but bulky goods such as plastic granules, fibres and foam. In practice road weight limits are often more restrictive than container capacity. Reefers are used for the cold chain, open-tops and flat racks for machinery and oversized items, and tank containers for liquids.

Dangerous goods transport (UN number, IMDG, ADR, IATA)

Flammable, corrosive, toxic, oxidising or environmentally hazardous substances are governed by mode-specific rules: the IMDG Code at sea, ADR by road, RID by rail and IATA DGR by air. Each substance is identified by a four-digit UN number (e.g. UN1823 sodium hydroxide, solid), a hazard class (1–9) and a packing group (I–III), all given in section 14 of the SDS. UN-approved packaging, class labels, a dangerous goods declaration and trained staff are compulsory; freight and insurance cost more than for general cargo, and some ships and ports refuse certain classes.

Explained in the trade handbook

Trade handbook