The CSC plate explained

What CSC is and where it came from

The CSC plate is the small, non-corrosive metal plate riveted to the door of every container cleared for international intermodal transport. It is the visible end of a longer chain of paperwork that begins with the International Convention for Safe Containers, adopted in Geneva on 2 December 1972 under a joint UN and IMO conference and in force since 6 September 1977. It sits inside the IMO regulatory framework alongside SOLAS and IMDG.

The 1960s saw container traffic grow from a niche idea into the dominant mode for general cargo, with national administrations writing their own structural rules. Without a common standard, a container legal in Hamburg could be rejected in New York or Yokohama. The CSC removed that friction. Two goals appear in the preamble: maintain a high level of safety for human life in handling and transport, and facilitate international transport through a single technical standard that contracting states recognise reciprocally.

The convention does three things. It defines the structural tests every container has to pass. It sets out how each unit is marked once it passes. And it specifies how that approval is kept alive over the container's working life. The IMO has issued several amendments since 1972, the most important being the 1993 amendments and later MSC resolutions that codified the Approved Continuous Examination Programme used by most large fleets today.

A container without a current CSC plate is not legal for international intermodal movement. Terminals refuse it, shipping lines refuse it, insurance does not respond on it. For a buyer this is binary: either the unit has a current CSC plate and full documentation, or it is a static storage box.

Tanax issues a CSC plate on every ISO Standard unit leaving the Bánovce nad Bebravou hall, fitted before paint cure with corner castings already in place.

What the plate carries (the fields)

The CSC convention specifies a minimum data set. The plate must be in English or French, lettering at least 8 mm high, with contrasting characters that survive the working life of the container.

• CSC SAFETY APPROVAL. The header. Without those exact words the plate is not a CSC plate.
• Country of approval and approval reference. Issued by the administration that signed off the type test. A Slovak unit typically carries an SK reference.
• Date of manufacture. Month and year. The anchor point for the entire inspection schedule. Year of manufacture is not encoded in the BIC code, only here.
• Manufacturer's identification number. The unit serial assigned by the production line.
• Maximum operating gross mass (MGW). In kilograms and pounds. 30 480 kg for a standard 20 ft, 32 500 kg for a 40 ft.
• Allowable stacking weight at 1.8 g. Vertical load the corner posts can take accounting for vessel motion. Standard ISO 1CC value 192 000 kg.
• Transverse racking test load. Lateral force the structure must resist without permanent deformation. Standard 150 kN per side.
• End-wall strength. Standard 0.4 P (fraction of maximum payload). Side-wall strength. Standard 0.6 P.
• First maintenance examination date or ACEP scheme number. The line that keeps the plate alive. Either the next examination date (NED) under the periodic scheme, or the registered ACEP number under the continuous scheme.

A modern CSC plate is usually a Combined Data Plate: CSC safety approval at the top, customs approval under TIR or the Customs Convention on Containers below, with BIC code reference and timber treatment marking grouped on the same plate. This is the format the Bureau International des Containers (BIC) recommends and what Tanax fits by default. If any field is missing or unreadable the plate is non-compliant and the unit must be re-presented for survey.

ACEP vs PES

The convention allows two maintenance regimes to run in parallel. A container sits under one or the other, both equally valid as long as the plate marking matches the regime in operation.

PES, the Periodic Examination Scheme. The default. First examination before the fifth anniversary of the date of manufacture. Subsequent examinations at intervals not exceeding 30 months. Each produces a new Next Examination Date (NED), marked on the plate once the unit passes.

ACEP, the Approved Continuous Examination Programme. For large operators. Instead of fixed-date surveys, the container is inspected at each repair or service event at an approved facility, and on a documented schedule between events. The operator runs the programme, the national administration approves it, and a single ACEP scheme number is registered and marked on the plate in place of the NED. Since 2010, every ACEP scheme is re-reviewed by the administration at least every ten years.

Which one fits depends on volume and operating model. PES suits owner-operators with smaller fleets, units in long-term static deployment, and any container not under a single corporate maintenance regime. ACEP is what major shipping lines and lessors run because their containers visit approved depots constantly.

A unit can switch between the two over its life. A container leaving a lessor's fleet for private ownership usually moves from ACEP to PES because the ACEP number no longer applies; the new owner schedules a PES inspection and marks the NED.

For a buyer ordering new from Tanax: the unit is delivered with the plate fitted and a clear path to first PES inspection at year five. If you operate an ACEP scheme, the BIC code and CSC reference can be filed against your scheme so the unit is covered from day one.

When a container needs revalidation

Revalidation is the act of refreshing the plate so the container stays legal for international transport. The rules are unforgiving.

Under PES:

• First examination must be completed before the fifth anniversary of the date of manufacture. A unit built in March 2026 has its first PES due no later than February 2031.
• Subsequent examinations at intervals not exceeding 30 months.
• Each examination produces a new NED stamped or marked onto the plate.

Under ACEP, the timing is event-based rather than calendar-based. The container is examined at each repair facility visit and on a documented schedule between events. The convention requires only that inspection frequency be no less safe than PES would deliver.

Triggers for revalidation outside the normal cycle:

• A major structural repair (corner post replacement, significant frame work) requires re-inspection regardless of cycle position.
• A change of ownership away from an ACEP-registered operator typically moves the unit back into PES and triggers a fresh examination.
• Damage that affects the structure, even with intact cosmetic appearance, can require an out-of-cycle inspection. A bowed bottom rail or a cracked corner casting weld is enough.
• A missing or illegible plate is treated as no CSC at all. The unit must be re-presented to a surveyor and a replacement plate fitted before international transport is legal again.

This matters in two buyer situations. Buying used: check the NED first; if the date has passed or is within a few months, the unit needs immediate inspection. Buying new for static storage: the first PES is still due at year five if you ever intend to move the unit intermodally again.

CSC + ISO 1CC stacking

CSC and ISO 1CC are different things that depend on each other.

ISO 1CC is the corner casting standard set out in ISO 1161 and tested under ISO 1496-1. A 1CC casting is a forged steel block with specific geometry, aperture dimensions and load rating. Eight are fitted per container. They are the only structural touch points with the outside world: cranes lift through them, twist-locks engage in them, lashing rods anchor to them, and one container stacks on the next through them.

CSC takes that hardware and certifies the whole container as a system. The stacking weight on the CSC plate (192 000 kg for a standard ISO unit) is the result the structure achieved when tested under ISO 1496-1, using the 1CC castings, welded frame, corrugated walls and floor as one assembly. The plate is proof of the test. The 1CC casting is the geometry that lets the result be used in the real world.

A container is only safely stackable up to nine high (the standard ISO 1CC rating under ISO 3874 lashing) if both conditions are met: castings have to be 1CC, and the CSC plate has to be current. A container with 1CC castings but expired CSC is structurally fine but not legally eligible for stack handling at a regulated terminal. A unit with current CSC but non-standard castings does not exist in the legal fleet, because the CSC test cannot be passed without 1CC geometry.

Tanax fits forged ISO 1CC castings to every ISO Standard unit before blast and paint. The CSC type test references those castings; the plate records the result.

How CSC interacts with EN 1090 EXC2

EN 1090 is the European standard for the execution of steel structures. EXC2 is the second of four execution classes, applicable to structural steelwork where failure has medium consequences. It covers welding procedures, welder qualification, base material traceability, dimensional tolerances, surface preparation and corrosion protection.

CSC and EN 1090 sit in different regulatory tracks. CSC is a global maritime convention administered by the IMO. EN 1090 is a European structural standard administered by CEN. They are not alternatives, they are layered.

EN 1090 EXC2 covers how the steelwork is fabricated: base steel certificates, welding procedure specifications (WPS), welder qualifications under EN ISO 9606, FARO arm dimensional measurement, blasting to ISO 8501 Sa 2.5 and the paint system to EN ISO 12944 C3. This is the upstream quality story.

CSC covers whether the finished container is fit for international transport: structural type test, corner casting geometry, plate marking and maintenance regime. This is the downstream certification story.

For a Tanax ISO Standard container, both apply. The welding line operates under EN ISO 3834-2 production-level qualification, which feeds the EN 1090 EXC2 chain. The same welds, castings and paint are then presented for CSC type approval. Both labels can be issued on the same unit because they describe the same physical thing from two regulatory angles.

For a buyer procuring under European public-sector rules (a defence framework, an emergency-services tender) the EXC2 line is what the procurement document usually demands. For a buyer moving the unit by ship or rail, the CSC plate is what the terminal demands. Tanax issues both on the same handover.

How to verify a container's CSC

For a buyer checking a unit before purchase or deployment, the verification is a short mechanical sequence.

1. Locate the plate. Usually on the left-hand door. A metal panel around 200 by 100 mm, riveted to the steel.
2. Read the header. Confirm CSC SAFETY APPROVAL is present and legible.
3. Check the country and reference. A valid plate has a country code (for example SK for Slovakia) and an approval reference issued by that administration.
4. Read the date of manufacture. Month and year. If the year is more than five years in the past, the unit must show a current NED or valid ACEP marking.
5. Read the gross mass and stacking values. MGW should match your order (30 480 kg for a 20 ft, 32 500 kg for a 40 ft). Stacking weight should be at or above 192 000 kg.
6. Find the NED or ACEP number. A future NED is fine. A past NED means the unit is out of cycle. An ACEP number means the unit is covered by a registered programme, which you can cross-check with the approving administration.
7. Check the BIC code on the container body. Four letters plus seven digits, painted on the side and door. The plate should reference the same owner prefix.

A unit bought from Tanax arrives with all of this at handover: CMR, CSC plate (fitted), multilingual manual, BIC code documentation. For a used unit on the open market the same checklist applies with extra weight on the NED. The most common reason a used container fails to deploy is an expired NED the buyer did not check. Read the date first.

FAQ

Is the CSC plate the same as the ISO 1CC certification? No. ISO 1CC is the corner casting standard, ISO 668 is dimensional, ISO 1496-1 is structural testing. CSC uses those ISO standards as inputs and certifies the container as fit for intermodal transport. ISO 1CC tells the crane operator how to lift the unit; CSC tells the terminal it is legal to lift.

What happens if the CSC plate expires while the container is in service? The container immediately becomes ineligible for international intermodal transport. Terminals refuse it. The owner has two options: schedule a fresh PES inspection and update the NED, or move the unit to ACEP coverage under an approved scheme. Until one is done, the unit can only be used for static storage.

Does a Tanax ISO Standard container ship with a CSC plate already fitted? Yes. Every new ISO Standard unit leaving Bánovce is delivered with the CSC plate fitted before paint cure, with country reference, date of manufacture, serial and structural values stamped or marked. Handover documentation includes the type test reference and BIC code allocation.

Can I choose between ACEP and PES at purchase? The plate ships with standard PES marking (first NED due before year five from date of manufacture). If you operate a registered ACEP scheme, the unit folds into your scheme after delivery and the ACEP number replaces the NED on the plate. Tanax can fit the ACEP decal at the factory if the scheme number is provided in advance.

Is the CSC plate accepted in all countries? The convention has been ratified by the majority of trading nations and the plate is reciprocally recognised between contracting states. Some non-contracting states have additional rules, but the CSC plate is the international baseline and every European state Tanax delivers into accepts it.

Do containers used purely for on-site storage need a current CSC? Strictly no. A unit that never moves intermodally does not legally need a current NED. But the moment it is relocated across an international border by truck, rail or ship, the plate has to be current. Most buyers who think they are buying for static storage end up moving the unit at least once.

Where on the container is the CSC plate located? Almost always on the left-hand door, fitted with rivets. On most modern units it is grouped with customs, BIC and timber treatment markings on a single Combined Data Plate, which is the Tanax default.

Who is responsible for keeping the plate current after delivery? The owner at the time inspection is due. On a leased fleet that is the lessor; on an owned unit, the buyer. Tanax remains the manufacturer of record and can issue replacement plates if the original is lost or damaged, but operational responsibility for revalidation sits with the owner.