CSC Safety Approval & Survey

What CSC is, and what it isn’t

CSC is the International Convention for Safe Containers, adopted at an IMO conference on 2 December 1972 and in force since 6 September 1977. It’s administered by the International Maritime Organization (IMO) in London, enforced by each contracting state through its maritime authority — in the United States that’s the US Coast Guard ↗, in the UK the MCA, in Australia AMSA, and so on.

CSC applies to any freight container used in international maritime transport. The treaty has two annexes: Annex I governs testing, inspection, approval and maintenance; Annex II sets structural safety requirements. The result is one practical fact: every container crossing an ocean border has to demonstrate that its steel is sound enough to be lifted, stacked, racked and slung.

What CSC does not cover, despite being routinely confused with all of these:

• Cosmetics — dents, paint condition, branding.
• The commercial condition grading system — CW (Cargo Worthy), WWT (Wind & Water Tight), IICL, etc. Those are trade conventions, not CSC. See the container condition guide for the grade hierarchy.
• Ownership, customs status, or titling.
• Domestic-only use. A container that never crosses an international ocean border is, strictly speaking, exempt from CSC. (See edge cases below — there’s a catch.)

The CSC Safety Approval Plate

The plate is the physical artifact that proves CSC compliance. Every container carries one — riveted, by convention, to the lower-left section of the left-hand cargo door, where it’s visible when the doors are closed.

Physical specification

• Permanent, non-corrosive, fireproof metal plate.
• Minimum dimensions 200 mm × 100 mm (roughly postcard-sized).
• The words CSC SAFETY APPROVAL stamped at least 8 mm tall; all other text and numbers at least 5 mm. Characters are stamped, embossed, or otherwise indelibly indicated.
• Modern factories (especially CIMC) often use a Combined Data Plate (CDP) that merges the CSC plate with the customs Tare/MGW data — same legal weight, different layout.

Required fields

1. The words CSC SAFETY APPROVAL
2. Country of approval and approval reference — e.g. GB-L/2345/CSC for a UK Lloyd’s-issued approval, or USA-USCG/.../CSC for a US-issued one.
3. Date of manufacture (month/year)
4. Manufacturer’s identification number of the container (or, for older units, the operator’s BIC code + serial — see the BIC Codes guide).
5. Maximum Operating Gross Mass in kg and lbs
6. Allowable stacking weight for a 1.8 g static load, kg and lbs (typically ≥ 192,000 kg for standard ISO boxes — that’s what supporting six fully loaded containers stacked above looks like in the spec sheet)
7. Racking test load value (transverse), kg and lbs
8. Optional: end-wall and side-wall strength values if non-standard
9. First and subsequent maintenance examination dates (month/year)

The "next examination date" field

One field on the plate matters more than all the others for day-to-day operations: the Next Examination Date (NED). The factory stamps an initial NED of manufacture-month + 5 years. After that first examination, the date is maintained one of two ways:

• Under PES (Periodic Examination Scheme): the original date is never re-stamped. Instead, a sticker/decal is applied to or adjacent to the plate at each successful re-examination, showing the new date. Read the most recent sticker, not the stamped date.
• Under ACEP (Approved Continuous Examination Programme): the NED field is not used. The ACEP marking takes precedence.

How a new container is certified

Before any container can be CSC-plated, the manufacturer’s design has to be type-approved and each individual unit production-inspected. Both jobs are done by an IACS classification society (Bureau Veritas, Lloyd’s Register, ABS, DNV, ClassNK, KR, CCS, RINA, IRS) acting on behalf of a flag-state Administration.

1. Type approval. A prototype of the container model goes through a standardized battery of ISO 1496-1 tests: lifting (from corner castings and forklift pockets), stacking (vertical load simulating multiple loaded containers above), racking (transverse and longitudinal forces at top corners), end-wall and side-wall strength, roof strength, floor strength, rigidity, weatherproofness, and door operation.
2. Series production inspection. Once the type is approved, every unit off the production line is inspected to the approved design by the society’s resident QA inspector. After sign-off, the manufacturer rivets the CSC plate to the left door.
3. Five-year initial validity. The plate is valid from the manufacture month/year stamped on it. The first periodic examination is due no later than five years from build.

Re-examination — ACEP vs PES

After the initial 5-year window, every CSC container must continue to be examined. The Convention permits exactly two approaches. This is the heart of the system.

The compliance clock

Scroll to run a container’s examination life under PES: certified at the factory, first exam due at year five, then a re-exam at most every 30 months for as long as it carries ocean cargo.

ACEP — the fleet-level programme

Approved Continuous Examination Programme. The container’s owner or operator commits to inspecting every container in their fleet continuously during normal operation — at every gate-in, gate-out, depot turn-in, and after every repair. The flag-state Administration approves the programme, not each individual container, after auditing the operator’s QA system, repair facilities, training, and recordkeeping.

ACEP containers carry an ACEP marking located as close as practicable to the CSC plate, formatted as:

ACEP / [CC] / [YYYY] / [number]

where CC is the ISO country code of the approving Administration (e.g. DK for Denmark, USA for the United States), YYYY is the year the programme was approved (not an expiry), and number is the programme’s assigned number. The USCG publishes its complete list of approved programmes ↗ publicly.

Why fleets use it: at scale, it’s cheaper than periodic surveys. A periodic survey costs $150–$300 per box. Inspecting a 200,000-container fleet every 30 months by individual survey would be $30M+. Building the inspection into the normal depot gate-in workflow — which is happening for damage assessment anyway — adds marginal cost.

PES — the per-container scheme

Periodic Examination Scheme. The original CSC re-examination model. Each container is surveyed individually at intervals not exceeding 30 months. The first re-examination must happen no later than 5 years from manufacture; every subsequent one, no more than 30 months from the previous one.

Each successful examination produces a CSC re-examination report (a PDF with photos, kept on file) and a sticker/decal affixed on or adjacent to the CSC plate showing the new next-examination date. Some surveyors apply the new sticker over the previous one; some apply a fresh plate. Either way, the most recent sticker is what’s read.

What an inspector actually does

A CSC re-examination takes 30–60 minutes per container on site. The inspector works a standardised checklist that covers nine zones, with dent-depth and damage tolerances referenced from IICL-6 (the Institute of International Container Lessors' published inspection criteria — the de facto numerical standard for pass/fail decisions).

Zone	What’s checked
Doors	CSC plate present and legible, BIC ID, hinges, cams, locking rods, gaskets pliable (no compression set, no tears), door operation, weather seal
Floor	Plywood condition, no soft spots, no through-holes, fasteners intact, no light leaks viewed from inside with doors closed
Front wall	Corner posts, top/bottom rails, corrugation integrity, lining
Sides	Corner posts, side rails, forklift pockets if fitted, dents and corrosion
Roof	Corner fittings, panel dents measured against IICL-6 tolerance (≤ 40 mm intrusion), roof bows, end rails
Corner castings	Eight in total. Cannot be patched, welded, or reshaped — only replaced. Aperture dimensions measured against ISO spec
Welds	Visual along seam lines; sometimes a tap/hammer test (clean ring = sound weld)
Repairs	Prior patches assessed for quality — correct steel gauge, full-penetration welds, no cold patches
Markings	CSC plate, BIC code, ISO size/type, owner code, tare/payload all legible

The inspector then issues a written survey report (PDF, with photos of every face and corner casting) and either:

• Passes the container — affixes a CSC re-examination decal showing the new next-exam date (survey date + 30 months), often with a QR code and surveyor’s serial.
• Fails it — issues a repair list itemising deficiencies with locations and required actions. No sticker is applied until repairs are done and a re-survey passes.

The survey houses — who’s who

Three distinct kinds of organisation can show up on a CSC survey report. They are not interchangeable, and understanding the difference matters when you’re hiring.

Classification societies (IACS members)

Non-governmental technical bodies that issue type approvals and certify surveys on behalf of flag-state Administrations. Container work is one slice of their business; hull classification is the bigger piece. The major ones doing container inspection:

Society	Origin
BV	Bureau Veritas — France, 1828
LR	Lloyd’s Register — UK, 1760 (oldest)
ABS	American Bureau of Shipping — USA, 1862
DNV	Norway (formerly DNV-GL)
ClassNK	Nippon Kaiji Kyokai — Japan, 1899
KR	Korean Register — South Korea
CCS	China Classification Society — dominates new-build
RINA	Italy
IRS	Indian Register of Shipping

All of the above can do new-build type approval, factory unit inspection, periodic re-examinations under PES, and ACEP programme approval/audit for fleet operators. In North America, BV, LR, ABS, and DNV maintain field offices in the major port cities (Houston, NYC/NJ, Long Beach, Savannah, Norfolk, Seattle, Vancouver).

Independent survey firms

Private companies that aren’t IACS members but employ surveyors qualified under a class society or under direct Administration authority. They specialise in containers — and for a single-site operator, they’re often the most practical option because they’re cheaper, faster, and locally available.

In the US/Canada market, the working independents you’ll actually encounter are firms like Maritime Cargo Services, Container Certification & Testing LLC, AIM Control Group, plus small regional marine-surveyor practices in every major port city. SGS (Swiss-headquartered global inspection firm) runs a tank & container services line and is another widely-available option.

A note on Unicon: the name comes up sometimes in the container-survey conversation but it’s ambiguous. Unicon Container Services is a Thai depot and M&R yard near Suvarnabhumi (Bangkok), 48,000 m², inspects to IICL for the major lines transiting Thailand — but it’s a depot operator, not a US-facing CSC inspector. Several unrelated firms also trade as "Unicon" in industrial-services contexts. If you’re in the US/Canada, lead with BV, ABS, LR, DNV, or a regional independent; consider Unicon if you’re doing work in Southeast Asia.

IICL — the standard, not a surveyor

The Institute of International Container Lessors is a trade association of major leasing companies (Triton, Beacon, SeaCube, et al.) founded in 1971. IICL is not a surveyor itself. It publishes:

• IICL-6 (effective 1 August 2016, superseding IICL-5) — the most widely used private inspection standard for dry containers, with numerical tolerance criteria for every component. Stricter than CSC’s plain-language structural requirements.
• IICL inspector qualifications — a written-exam certification that individual surveyors carry to prove they know the criteria. Most class-society and independent surveyors are IICL-certified.

A container "graded IICL" has passed an IICL-standard inspection on top of CSC. That’s relevant for off-hire returns to leasing companies but not strictly required for normal export — a CSC-current container that doesn’t meet IICL thresholds (dents past the numerical limits, for example) can still be loaded for export.

Reading the markings — ACEP vs CSC sticker

A modern in-service container almost always carries both of these in close proximity on the left-hand door:

Marking	CSC Safety Approval Plate	ACEP decal (if applicable)
What it is	Riveted metal plate, ≥ 200 × 100 mm, stamped/embossed	Adhesive sticker or painted marking
Permanent?	Yes — lifetime of the container	Persistent for the life of the operator’s programme
Content	Approval country/ref, manufacture date, MGW, stacking weight, racking, NED	ACEP / CC / YYYY / number
Updated?	Original stamping never changes; PES sticker overlays the date	Updated only if programme number changes

The single-site operator workflow — exporting a container that’s been sitting

This is the practical part. The scenario: you bought one or two containers a few years ago for ground storage. The plate’s next-examination date is in the past. You want to ship one of them internationally — your own goods, a project, a relocation. Here’s the full workflow.

Step 1 — Confirm CSC actually applies

If the box is going on a ship across an international ocean border, CSC applies. Full stop. There is no exemption for "personal use," "one-time export," "one-way," or "I’m shipping my own stuff." Carriers will not load an out-of-CSC container, and ports will not handle one. Air or land-only moves don’t require CSC — but if there’s a sea leg, it applies.

Step 2 — Find an inspector

Options, in the order a typical US operator finds them:

1. Ask the carrier you’re booking with. Maersk, MSC, ONE, CMA CGM, Hapag-Lloyd, Evergreen, etc. all maintain approved-surveyor lists for shipper-owned container (SOC) export bookings. They’ll usually name three or four firms in your area.
2. A class-society field office in your nearest port city — BV, LR, ABS, DNV all have US offices in major port metros (Houston, NYC/NJ, Long Beach, Savannah, Norfolk, Seattle, Vancouver).
3. An independent surveyor. Search "CSC surveyor [your port city]" and you’ll find firms like Maritime Cargo Services, Container Certification & Testing LLC, AIM Control Group, plus small regional practices in every port metro.
4. A container resale dealer in your region — many have in-house IICL-certified surveyors who’ll come on-site for a fee.

Avoid anyone who can’t produce credentials. A "CSC sticker" from someone unqualified is worthless and will be rejected by the carrier at the gate. Look for: IICL inspector card, class-society authorisation letter, or direct Administration approval.

Step 3 — Schedule and prep

Lead time	1–3 weeks to book the survey; longer in winter or remote areas
Duration	30–60 minutes on site per container
Cost	$150–$300 base survey fee, plus $100–$300 travel if the site is remote
Prep	Container empty, swept clean, doors operational, all six sides accessible — including under the corners (have a forklift available if needed)
Documents	Original bill of sale (proof of ownership), photos of any prior repairs, previous CSC reports if you have them

Step 4 — The survey

The inspector works the nine-zone checklist above. The items most likely to fail on a container that’s been sitting for a few years:

Failure	Why it happens	Typical repair
Floor soft spots / rot	Water ingress through doors over time	$300–$1,500 (patch or replace)
Door gasket failure	UV exposure + compression set; rubber degrades	$100–$300 per door
Door alignment / cam binding	Settling on uneven ground, bent rods	$50–$300
Rust through on bottom rails	Sitting directly on grass or gravel without bearers	$200–$1,000
Corner casting damage	Forklift hits during placement	$500–$1,500 (replacement only — no patching)
Roof dent past 40 mm intrusion	Tree branches, snow load, walking on roof	$200–$800 (often left if borderline)
Missing/illegible CSC plate	Painted over, corroded, or removed	$200–$500 + class-society admin to re-issue

Step 5 — If it fails

You get a written repair list. Hire a container repair shop (many surveyors are affiliated with one), or do the work yourself if you have a stick welder and the skills. Book a re-survey after repair, usually a discounted return visit ($75–$150).

Step 6 — If it passes

The surveyor applies a CSC re-examination decal to or adjacent to the plate, showing the new next-exam date (survey date + 30 months). You receive a PDF report with photos. The container is now CSC-current for 30 months.

Step 7 — Booking the voyage

Present the survey report to the carrier when booking. Expect the carrier (or their terminal operator) to do their own gate inspection when the container arrives at the port — they’re checking for damage that may have occurred since the survey, and they reserve the right to refuse the container regardless of your paperwork. Arrive 2–3 days before vessel cut-off, not on the day. Build in margin.

What can go wrong

• Failed survey close to a sailing deadline. Repair lead times can be 1–3 weeks. Book your survey early — at least 4–6 weeks before vessel cut-off.
• Carrier rejects the container at the gate despite a valid survey — usually for damage in transit to port, or pre-existing issues the surveyor missed. Have a backup plan.
• Lost or unreadable CSC plate. Possible to replate (see below), but requires class-society administrative action and adds time + ~$500.
• Ownership/title gaps. If you bought the container years ago at a depot auction with no paperwork, some carriers want a chain of custody. Have your receipts.
• Old stenciling. If the original owner’s branding ("MAERSK" in big blue letters, etc.) is still visible, repaint or overstencil neutral before shipping. Not a CSC issue, but a carrier-acceptance issue.

Edge cases

One-way / one-trip containers

A container shipped once internationally and then sold, donated, or scrapped at destination. As long as the CSC plate is current at the time of loading, the voyage is legal. The container doesn’t have to return — the CSC plate simply lapses with the next-exam date thereafter. This is the model for "new one-trip" containers sold inland: they crossed once, the CSC is still valid for a few more years on paper, and then it lapses.

Domestic-only containers

Pure storage or domestic road/rail transport doesn’t legally need a current CSC. But: once a plate lapses, returning the container to international service requires a fresh full re-examination (and possibly plate re-issuance if the plate is degraded). Losing CSC isn’t permanent, but reinstating it costs money and time. For high-value containers (reefers, tanks) operators try to keep CSC current even during storage to preserve resale value as a cargo-worthy box.

Stenciling and stickers — what’s permanent

• Permanent: CSC plate (riveted, lifetime), BIC code (paint-stencilled to ISO 6346 standard, redone in the same position each repaint), Tare/MGW markings, owner code.
• Replaceable: CSC re-examination decal (replaced each PES cycle), ACEP decal (lifetime of programme), carrier inspection-sticker dots, customs/seal numbers.

A CSC plate is never painted over. A repaint shop must mask it. If yours has been painted, scrape it clean before the survey or you’ll fail on legibility.

Lost or unreadable CSC plate

Possible to remedy, but expensive:

1. Contact a class society (BV, LR, ABS, DNV) — they may be able to re-issue based on the manufacturer’s original type-approval records if you have the BIC code and serial.
2. If original records can’t be located, a full re-test of the container against its design type may be required, which for an in-service unit is impractical — at which point the container is effectively scrap for international use.
3. Cost: typically $300–$800 in class-society admin fees plus a full survey, plus the cost of a new plate. Sometimes a surveyor will simply rivet a replacement plate during the re-examination if the original is degraded but the container is identifiable from other markings.