The liquid-tight shell designed to contain the cargo.
- Deck tank – A cylindrical gravity cargo tank, secured to transverse cradles on the cargo tank deck and used for specialised cargo.
- Gravity tank – A cargo tank with design pressure not exceeding 0.7 bar gauge. Independent tank – A tank entirely separated from the hull structure and not contributing to the strength of the ship. Tanks of this type are used for transport of liquefied gases, molten sulphur and bitumen products.
- Integral tank – A tank that contributes directly to the strength of the hull structure and is contigous with it.
- Pressure tank – An independent cargo tank type C designed to withstand an internal pressure in excess of 0.7 bar gauge.
- Separate tank – A gravity cargo tank which is not fully integrated into the hull structure but has a limited degree of attachment, for example, to transverse primary members only.