What is an ISO Tank Container? Types, Sizes, Capacity

Nantong CIMC ISO Tank

In the industry of logistics and transportation, the importance of ensuring the safe, efficient, and cost-effective transfer of liquids is paramount. This is where the ISO tank container, a pivotal asset in the transportation of liquids, plays a crucial role. ISO tank containers offer a versatile solution for shipping various types of liquids, including chemicals, food-grade products, and gasses like LNG. This article explores the various aspects of ISO tank containers, from their basic definitions and uses to specific types, benefits, and considerations for choosing the right container.

What is an ISO Tank Container?

An ISO tank container, often simply called an ISO tank, is a stainless steel container held within a 20-foot ISO frame that meets the International Organization for Standardization (ISO) standards. These robust containers ensure consistent dimensions and fittings meaning the container is safe, reliable, and suitable for multiple transportation modes including ship, rail, and road. ISO tanks are specifically designed to securely store and transport liquids and gasses, minimizing the risk of leaks and spills during transit.

Uses of ISO Tank Containers

ISO tank containers are highly valued for their versatility and efficiency. They are commonly used to transport:

  • Liquids: From non-hazardous products like water, juices, and oils to hazardous chemicals and fuels, ISO tanks can handle a wide range of liquids.
  • Gasses: Liquefied natural gas (LNG), industrial gasses like oxygen and nitrogen, and even compressed natural gas (CNG) can be safely transported in specially designed ISO tank containers.
  • Powders and Granules: Food-grade powders like flour and sugar, as well as plastic pellets and other dry bulk materials, can be efficiently transported using ISO tanks with special loading and unloading features.

Their ability to maintain specific temperatures and control conditions makes them ideal for sensitive products, ensuring that they reach their destination in optimal conditions.

What Liquids Can Be Carried by an ISO Tank?

The specific types of liquids suitable for ISO tank containers depend on the tank’s internal lining and pressure rating. Here’s a breakdown:

  • Food-grade liquids: Stainless steel tanks with a food-grade lining are ideal for transporting edible liquids like beverages, oils, and syrups.
  • Chemicals: Depending on the specific chemical, tanks with different linings (e.g., epoxy) and pressure ratings are used for safe and compliant transportation.
  • Hazardous materials: ISO tanks designed and certified for hazardous materials adhere to strict regulations and incorporate additional safety features.
  • LNG (Liquefied Natural Gas): The use of ISO tanks for LNG is particularly noteworthy as they are equipped with super insulation to handle the cryogenic nature of liquefied gasses. This makes ISO tanks an excellent choice for transporting LNG because of their safety features and ability to maintain the very low temperatures required to keep the gas in liquid form.

Benefits of ISO Tank Containers

ISO tank containers offer several advantages over other forms of bulk transport:

  • Safety and Security: These containers are constructed with robust materials like stainless steel, providing a secure environment for transporting hazardous chemicals. They are leak-proof and equipped with safety valves, reducing the risk of spills and leaks during transit
  • International Approval and Quality Assurance: ISO tank containers are internationally approved and come with quality assurance, ensuring their reliability and safety during transportation.
  • Cost-effectiveness: Their ability to be reused, their durability, and their economies of scale reduce handling costs and make them a cost-effective option for long-term and repeat use.
  • Environmental Impact: ISO tank containers are designed to combat product spillage and leakage, especially during long journeys, reducing fuel consumption and carbon dioxide emissions by up to 70%. They contribute to environmental sustainability by minimizing the risk of spills and leaks.
  • Efficiency: Their standardized dimensions allow for easy handling and transfer between different modes of transport, reducing downtime and making them a convenient option for transporting liquids.
  • Versatility and Compatibility: ISO tank containers are versatile and capable of transporting a wide range of chemicals, reducing the need for multiple types of transportation equipment. They are compatible with various types of chemicals, endure extreme conditions, and are available in different sizes to meet diverse transport requirements.

Types of ISO Tank Containers

There are several types of ISO tank containers tailored to meet specific needs, industry standards, and regulations, ensuring the safe and secure transport of liquids. Here are the ISO tank container types available:

  • Reefer Tanks: Equipped with powerful refrigeration units, these tanks are essential for transporting perishable liquids like juices, dairy products, and pharmaceuticals. They can maintain consistent low temperatures to ensure cargo freshness and safety.
  • Gas Tanks: Designed with robust construction and specific safety features, these tanks are suitable for the safe carriage of various gasses, including liquefied natural gas (LNG), industrial gasses like oxygen and nitrogen, and even compressed natural gas (CNG).
  • Silo Tanks: Intended for powders or grain transport, these tanks often resemble silos and incorporate features like pressure relief valves and filling hatches on top for efficient loading and unloading. They may also have internal compartments or dividers to accommodate different types of dry bulk cargo.
  • Food-Grade Tanks: These tanks are specifically designed to meet stringent hygiene standards for transporting edible liquids like beverages, oils, syrups, and even some dry bulk food items like flour or sugar. They typically feature a smooth, corrosion-resistant stainless steel interior and may have a special non-porous lining to prevent contamination and ensure product quality.

Moreover, ISO tanks are further categorized based on their purposes such as:

  • T1 ISO tank: Designed for light liquid transport.
  • T4 ISO tank: Suitable for non-hazardous edible and non-edible oils.
  • T11 ISO tank: Certified for non-hazardous chemical transport.
  • T14 ISO tank: Specifically for hazardous chemicals.
  • T50 ISO tank: Used for liquefied petroleum gas and ammonia gas transport.
  • T75 ISO tank: Tailored for liquefied gas transportation.
  • Rubber-lined ISO tank: Constructed for acid-based chemical transport.

Sizes and Capacity of ISO Tank Containers

ISO tank containers typically come in the size of a standard 20-foot shipping container but can vary in capacity (typically 20ft or 40ft long, 8ft wide, and 8ft or 9ft high). Most tanks have capacities ranging from 14,000 to 26,000 liters, providing ample space for large-scale liquid transport. The specific size and capacity will depend on the liquid type, the required transport conditions, and regulatory requirements.

ISO Tanks vs Flexitanks

When comparing ISO tanks to flexitanks, several differences become apparent although both are used for transporting liquids. Flexitanks are a cost-effective, one-time-use option suitable for non-hazardous liquids. They are essentially large bags installed in conventional shipping containers. However, ISO tanks are more expensive than flexitanks but offer greater durability and versatility.

While flexitanks can be a good option for certain shipments, ISO tanks which are made from stainless steel, are preferable for long-distance transportation containing hazardous materials, high-volume shipments, repeated use, and where maintaining specific conditions is crucial.

How to Choose the Right ISO Tank Container

The versatility of ISO tank containers makes them a popular choice for transporting a wide range of bulk cargo. However, with various types and configurations available, choosing the right ISO tank can seem overwhelming. Here’s a comprehensive guide to help you select the ideal container for your specific needs:

1. Identify Your Cargo

  • Type of product: The first step is to determine the exact product you’ll be transporting. This includes considering its physical state (liquid, gas, powder), any hazardous properties, and temperature sensitivity.
  • Volume and weight: Knowing the total volume and weight of your cargo is crucial. This will help you choose an ISO tank with the appropriate capacity and weight limitations.

2. Consider Compatibility

  • Tank lining: Depending on your cargo, a specific tank lining might be necessary. For example, food-grade liquids require a non-porous lining to prevent contamination, while some chemicals might necessitate an epoxy lining for optimal compatibility.
  • Pressure rating: Certain liquids, especially hazardous materials or gasses, require tanks designed to withstand specific internal pressure levels.

3. Evaluate Your Journey

  • Transportation mode: Will your ISO tank be transported primarily by truck, train, or ship? Intermodal compatibility is essential if your journey involves multiple modes of transport.
  • Temperature control: For temperature-sensitive products, choose a refrigerated or heated ISO tank to maintain optimal conditions throughout the journey.

4. Think about Additional Features

  • Loading and unloading: Depending on your cargo and facilities, specific features like top discharge hatches or bottom outlets might be necessary for efficient loading and unloading.
  • Cleaning requirements: Consider the ease of cleaning the ISO tank interior, especially if you plan to transport different products. Some tanks may have specialized cleaning features.

5. New vs. Used ISO Tanks

  • Budget: New ISO tanks offer the latest safety features and optimal performance, but come with a higher initial cost. Used tanks can be a more budget-friendly option, but thorough inspection and certification are crucial.

Additional Tips:

  • Consult with a reputable ISO tank supplier: Experienced suppliers can provide valuable guidance based on your specific cargo and transportation needs.
  • Consider leasing options: Leasing ISO tanks can be a good choice for companies with occasional bulk transport needs or those who prefer to avoid a large upfront investment.
  • Focus on safety: Always ensure the ISO tank you choose meets all relevant safety regulations and is certified for transporting your specific cargo.

By following these steps and considering these additional factors, you’ll be well-equipped to select the right ISO tank container for your bulk transportation needs. Remember, the ideal container ensures the safe, efficient, and cost-effective movement of your valuable cargo.


ISO tank containers are indispensable in the global transport of liquids, providing a secure, efficient, and eco-friendly solution. Whether transporting food-grade products, chemicals, or gasses like LNG, these containers offer a range of benefits that make them a preferred choice for businesses worldwide. By understanding the different types and specifications of ISO tanks, businesses can make informed decisions to optimize their logistics operations and ensure the safe delivery of valuable liquid cargo.