National Portable Storage Association

Container basics

shipping container

A shipping container is a standardized steel box used to move freight by ship, rail and truck without unloading the goods. Most are rectangular, closed boxes with doors at one end. Many are reused for storage after their sea service ends.

Why it matters

The shipping container is the base product of the portable storage industry. Operators buy used units from the shipping world, then rent or sell them for storage, job sites and conversions. Standard sizes and strong corner fittings let one box move on a truck, train or ship. A common mistake is to use shipping container and portable storage container as if they mean the same thing. A portable storage container is a container sold or rented for storage, and it may be a shipping container, a purpose-built unit or a modified one. Ask what the unit was built for, how old it is and what grade the seller assigns before you plan lifting, stacking or delivery.

Read: Shipping container sizes and dimensions for rental fleets

Definition source: en.wikipedia.org

Related terms

intermodal container

An intermodal container is a standardized, reusable container that can move between ships, trains and trucks without unloading the cargo. It has fittings for handling, securing and stacking. Most dry freight containers use a closed steel box with doors at one end.

ISO container

An ISO container is a freight container built to the ISO series 1 standards, such as ISO 668 for classification and dimensions and ISO 1496 for specification and testing. The standards let boxes fit the same ships, trucks and handling gear worldwide.

portable storage container

A portable storage container is a container made for rent or sale as movable storage. NPSA describes portable storage containers as ISO shipping containers retired from international shipping and offered on the domestic market. In practice the term also covers other portable units.

storage container

A storage container is a container used to store goods, often a retired shipping container, that sits on a site and keeps items dry and secure. Companies rent or sell them in several sizes and conditions. Many have double doors on one end and can be lifted or moved on a truck.

used container

A used container is a container that has served a working life, usually at sea, before being sold or rented for storage. Sellers grade used units, often as cargo worthy, wind and water tight or as-is. The grade affects price, appearance and how well the unit keeps out water.

corten steel

Corten steel is a weathering steel alloy used for the walls and roof of most standard shipping containers. It contains copper and chromium. When it is exposed to weather, it forms a stable, rust-like surface layer that protects the metal below. COR-TEN began as a trademarked name.

All 220 terms

For the industry

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