An ISO tank container is a stainless steel tank mounted inside a standard 20-foot shipping container frame. It's designed to transport liquid bulk products — chemicals, food-grade liquids, pharmaceuticals, and other liquids — by ocean, rail, and truck using the same intermodal infrastructure as standard dry containers.
ISO tanks are the most efficient way to ship liquid bulk products internationally. They carry 21,000 to 26,000 liters (5,500 to 6,800 gallons) per tank, they're reusable, they fit standard container handling equipment, and they can move seamlessly between vessel, rail, and truck without transferring the product.
ISO tank specifications
A standard ISO tank fits a 20-foot container frame (20' x 8' x 8'6"). The tank itself is cylindrical stainless steel (typically 316L grade) with a capacity of 21,000-26,000 liters depending on the design. Working pressure ranges from 1.5 to 10 bar depending on the product requirements. ISO tanks are built to international standards (ISO 1496, ASME, and ADR/RID for hazmat) and are approved for multimodal transport.
The tank includes a manhole for loading and inspection (top), a bottom discharge valve for unloading, pressure relief valves, and optional heating coils for temperature-sensitive products. Some ISO tanks are lined (rubber, polyethylene, or epoxy) for corrosive products, and some are insulated or equipped with steam heating capability.
How much does an ISO tank hold?
Standard capacity is 21,000-26,000 liters (approximately 5,500-6,800 US gallons or 140-170 barrels). The exact capacity depends on the tank design and the fill limit — most ISO tanks can only be filled to 80-95% of total volume depending on the product's expansion characteristics and hazmat classification.
For comparison, a domestic tanker truck holds approximately 6,000-7,000 gallons, so an ISO tank carries roughly the same volume as one tanker truck load. The advantage is that the ISO tank can travel by ocean, rail, and truck without the product being transferred between containers.
When to use ISO tanks
International liquid bulk shipments. ISO tanks are the standard method for shipping liquid chemicals, food-grade products, and other bulk liquids internationally. They fit on container vessels alongside standard dry containers.
Hazmat products. ISO tanks are designed and certified for hazardous material transport. They're the preferred method for international hazmat liquid shipping.
Temperature-sensitive products. ISO tanks with heating coils or insulation maintain product temperature during ocean transit — critical for products that solidify or degrade at ambient temperatures.
Reusable and cost-effective for regular shipments. Unlike flexitanks (single-use liners inside dry containers), ISO tanks are reusable. For regular shipments of the same product, the per-shipment cost of an ISO tank is lower than disposable alternatives.
ISO tanks vs other liquid bulk methods
ISO tank vs flexitank: ISO tanks are reusable, handle hazmat, and work for a wider range of chemicals. Flexitanks are single-use, cheaper per trip for non-hazmat products, but can't handle hazmat or most chemicals.
ISO tank vs drums/IBCs: ISO tanks are far more cost-effective for bulk volumes. Drums and IBCs make sense for small quantities or when the receiver can't handle bulk unloading.
How Total Connection handles ISO tank shipping
As a licensed NVOCC, we manage ISO tank ocean freight globally — including tank sourcing, booking, hazmat documentation, drayage at both ends, and delivery coordination. Our chemical freight expertise means we match the right tank specification to your product's requirements.
Call 732-817-0401 or request a quote.
