The Ultimate Guide to Shipping Container Markings, CSC Plates & Survey Certificates: What You Need to Know

When exporting a shipping container also known as – Conex Box – Cargo Container, Intermodal Container or Sea Can, it’s essential to understand the various markings, certifications, and plates that ensure compliance, safety, and structural integrity.

The 1972 the International Convention for Safe Containers (CSC) established by the International Maritime Organization (IMO), set global safety and inspection standards for shipping containers. It ensures containers are structurally sound, properly inspected, and safe for transport overseas.

Key Accomplishments of the CSC-

1. Set Universal Safety Standards – Established design, construction, and maintenance requirements to prevent structural failures and accidents.
2. Mandated CSC Plates – Requires every container to have a CSC Plate displaying certification details, weight limits, stacking capacity, and inspection records.
3. Required Periodic Safety Inspections –The first inspection is required within 5 years of the container’s manufacture date. After that, inspections must be conducted at least every 30 months (2.5 years). The container is checked for structural integrity, corrosion, damage, and compliance with CSC safety standards.
4. Enhanced Global Shipping Safety – Reduced accidents, cargo loss, and delays by enforcing strict compliance across all shipping nations.

What Do The Shipping Container Markings Mean?

1. Container Number- A shipping container number consists of a four-letter prefix (owner code and equipment category) followed by a six-digit serial number and a check digit, ensuring unique identification and facilitating accurate tracking
   • Owner Code (First 3 Letters): Identifies the owner or operator of the container.
   • Equipment Category Identifier (Fourth Letter): “U” typically indicates a freight container, while “J” is for detachable freight container-related equipment and “Z” for trailers and chassis.
   • Serial Number (Next 6 Digits):  A 6-digit unique serial number assigned to each container by the owner.

2. Check Digit – A digit used to validate the accuracy of the owner code and serial number.

3. Iso Code- A 4-character sequence indicating container dimensions and type.
   • The first digit = Length (e.g., “2” means 20 feet).
   • The second digit = Height (e.g., “5” means 9’6” high cube).
   • Remaining letters/numbers indicate container type (e.g., “G1” for general purpose and “U1” is for open top).

4. Weight & Capacity Panel – Includes:
   • Maximum Gross Weight (total allowable weight, ~30 metric tons).
   • Tare Weight (empty container weight, 4-10 metric tons).
   • Payload (maximum cargo weight = gross weight minus tare weight).
   • Maximum Cargo Volume (important for bulky but lightweight cargo).

5. Height Warning– Height markings are required on shipping containers exceeding 8 ft., 6 in.in height. They typically appear as measurement figures on a yellow background with a black outline and are positioned in the right-hand corner of each side of the container.

6. CSC Plate- A CSC (Convention for Safe Containers) plate is a safety approval plate affixed to a shipping container, certifying that it meets the International Convention for Safe Containers (CSC) standards. It is typically a metal plate located near the container doors and contains key structural and safety information.

7. Warning & Handling Instructions- Provides safety guidelines for loading, unloading, stacking, and transportation of container to ensure proper handling and prevent damage or accidents.

These markings help track, transport, and verify containers worldwide, ensuring efficiency and compliance in international shipping

CSC Plate and what it looks like?

Let’s take a closer look at the Convention for Safe Containers (CSC) plate. This safety certification plate is mandatory for all containers used in international shipping, confirming that the unit has been inspected, meets structural integrity standards, and is safe for transport under heavy loads and harsh conditions.

Where Do You Find a CSC Plate?

1. What is a CSC Plate?
   • A CSC plate, or Combined Safety Certificate plate, is a small, standardized metal plate fixed to the doors of ISO containers, indicating whether the unit is safe for international transport.
   • It contains crucial information about the container’s safety, including the date of manufacture, maximum weight capacity, and the next examination date (NED).
   • The plate is a vital part of the Convention for Safe Containers (CSC), which sets safety standards for ISO shipping containers.

What Information Does a CSC Plate Contain?

A CSC plate typically includes:

• Approval Reference Number – Identifies the issuing regulatory body.
• Date of Manufacture – Indicates when the container was built.
• Owner & Manufacturer Details – Specifies who owns and produced the container.
• Container Identification Number – Matches the unique ID found on the container itself.
• Maximum Gross Weight – The highest allowable weight, including cargo.
• Allowable Stacking Weight – How much weight the container can support when stacked.
• Racking Test Load Value – Confirms the container’s ability to withstand sideways pressure.
• Next Inspection Date – If applicable, the date of the next required safety check.

When Should a Container Be Inspected?

• Before Export – Ensure compliance with CSC safety regulations.
• If Damaged – Any structural damage must be inspected and repaired.
• After Modifications – Any container that has been altered (e.g., adding doors, windows, or reinforcements) must be re-certified.
• For Leasing or Sale – To verify the container is safe and cargo-worthy.

Why Update a CSC Plate?

• CSC plates have an expiry date, typically 5 years from the date of manufacture for single-trip units, and require periodic renewal through inspection and recertification.
• Even if the container is under an Approved Continuous Examination Program (ACEP), it still needs to be inspected and recertified to ensure it remains safe for transport.
• If a container is modified or damaged, a new inspection is required before the CSC plate’s expiry date to ensure continued safety.

How to Update a CSC Plate

• Contact an Industry Professional:  You need to contact a company or organization that specializes in container inspections and recertification, such as those accredited by the Institute of International Container Lessors (IICL), ABS, or BV.
• Detailed Inspection:  The inspector will conduct a thorough examination of the container’s structural integrity, looking for any damage, corrosion, or other issues that could compromise safety.
• Recertification:  If the container passes inspection, the inspector will issue a new CSC plate or update the existing one with a new Next Examination Date (NED).
• Documentation: Ensure all necessary documentation, including previous inspection records, is complete and available.

Failure to comply with CSC inspection requirements can lead to shipping delays, fines, or rejection at ports.  A valid CSC plate ensures your container is safe, compliant, and ready for international transport. Whether buying, leasing, or shipping a container, always check the CSC plate for certification details.

Survey Certificate is Essential for Export Shipping Containers – Whether Leased or Purchased

A survey certificate for a shipping container is issued by a certified container inspector or marine surveyor, it is an official document confirming that the container meets safety and shipping standards. These professionals work under industry regulations and guidelines.

What is Included in a Shipping Container Survey Certificate?

It typically includes the following details:

1. Container Identification & Details
   • Container Number
   • Size & Type (e.g., 20’ Standard, 40’ High Cube)
   • Owner/Lessor Information
   • Manufacture Date & CSC Plate Verification
2. Structural Condition & Inspection Findings
   • Exterior Condition – Checks for dents, rust, corrosion, and integrity of panels.
   • Interior Condition – Ensures no leaks, flooring damage, or contamination.
   • Doors & Seals – Verifies they open/close properly and are watertight.
   • Roof & Corner Posts – Inspected for cracks, bends, or major damage.
   • Floor Load Capacity – Ensures it can handle cargo weight safely.
3. Certification & Compliance
   • Cargo Worthy Certification (CW) – Confirms it meets international shipping standards.
   • IICL or Wind & Watertight (WWT) Rating – If applicable.
   • Surveyor’s Name & Certification Number – Identifies the authorized inspector.
   • Inspection Date & Validity Period
4. Remarks & Recommendations
   • Notes on repairs needed (ALL REPAIRS MUST BE COMPLETED).
   • Approval for export or rejection based on findings.

This certificate is essential for shipping lines and customs clearance, ensuring that the container is safe, compliant, and ready for transport

When exporting a shipping container, ensuring it meets safety, compliance, and certification requirements is crucial to avoid costly delays and regulatory issues. Container Sales Group specializes in export container preparation, providing certified, cargo-worthy containers that meet CSC, ISO, and IICL standards.

Need a Certified Container for Export? We’ve Got You Covered

Since 1998 Container Sales Group has been working with International Freight Forwarders and Companies in need of a Cargo Worthy (CW), IICL-certified container or New/One-Trip Cargo Containers.  We also have a network of Container Surveyors to provide a certified CSC Survey Certificate to ensure compliance on all of our conex boxes.  Call us today at 888-320-5938 to learn more.

Container Sales Group has been committed to providing New, Used, and Specialty Freight Containers across the United States. We take pride in offering honest pricing, fast response times, and exceptional customer service, ensuring our customers receive high-quality intermodal containers at direct, wholesale prices.