If your company participates in CTPAT — the Customs Trade Partnership Against Terrorism — container inspection isn’t a suggestion. Members are expected to inspect empty containers before loading, using a structured process, and to document that it happened.

The seven-point inspection is that process. It’s simple enough that a warehouse team can run it in a few minutes, and it exists because concealed compartments in container structures are a real and recurring smuggling method.

Why the inspection exists

A container has a handful of hollow structural spaces that look solid from the outside. Someone with access to an empty container and a few hours can build a false wall, hollow out a floor section, or pack a ceiling cavity. Once the legitimate cargo goes in on top, nothing looks unusual.

The seven-point inspection is designed to catch exactly that: not the cargo, but the container itself. It’s performed on the empty box, before loading, which is the only moment the structure is fully visible.

The seven points

1. Front wall

Stand at the doors and look down the length of the box. Check that the front wall’s interior length matches the container’s exterior length — a false front steals interior depth. Look for repairs, mismatched paint, new welds, or blocked ventilation openings.

2. Left side

Inspect the full run of the wall. Container walls are corrugated; the corrugation pattern should be uniform, unbroken, and consistent from end to end. Repairs, patches, and unusually flat sections deserve a closer look. Tap along the wall — a solid, dull sound where you expect a hollow ring suggests something behind the panel.

3. Right side

Same process. Compare the two sides against each other; asymmetry is a useful signal.

4. Floor

Container floors are typically marine plywood over steel cross-members. The floor should be level and of uniform height. A raised floor section, new or unusually clean plywood among weathered boards, or fresh fasteners are all worth investigating. Compare interior floor height against the exterior underside.

5. Ceiling and roof

Look up. Blocked vents, patches, new welds, or a ceiling that appears lower than the container’s exterior height all warrant a second look. Roof cavities are a common concealment location because they’re the hardest for an inspector to reach.

6. Inside and outside doors

Check that the locking mechanisms, hinges, and door hardware are original and secure. Look for loose or mismatched rivets, fresh tool marks, or door panels that have been opened and re-welded. Door hardware tampering allows access without ever touching the seal.

7. Outside and undercarriage

Walk the exterior. Inspect the support beams underneath — they should be visible, evenly spaced, and free of added boxes or plates. Any structure attached beneath the container that isn’t part of the original design is a finding.

Documenting it

An inspection that isn’t recorded didn’t happen, as far as an audit is concerned. Good practice:

• Use a standard checklist with all seven points and a sign-off line
• Record the container number, the date and time, and the inspector’s name
• Photograph each point, particularly the interior corners, floor and ceiling
• Note the seal number applied after loading
• Retain records for the period your compliance program requires

Some programs use a more detailed seventeen-point inspection for trailers, which adds points specific to refrigeration units, fifth wheels, and tires. For ocean containers, seven points is the standard baseline.

Where it fits in the drayage chain

The inspection happens before loading, which means it belongs to whoever controls the empty container — typically at the stuffing location, whether that’s your own warehouse, a container freight station, or a transload facility.

What matters for drayage is what comes after: the container is sealed, and from that moment the chain of custody has to hold. Seal numbers recorded on the interchange receipt at every handoff, drivers who verify rather than assume, and a carrier whose equipment and yard are under its own control. Our post on container seals and ISO 17712 covers the sealing side.

If your export containers are being stuffed at a third-party facility, ask directly whether seven-point inspections are performed and how they’re documented. It’s a reasonable question and the answer tells you a lot about the facility. Go Drayage’s container freight station operates under U.S. Customs bond #LBR8.

Common findings that turn out to be nothing

Most anomalies have ordinary explanations. Containers are twenty-year-old steel boxes that get repaired constantly. A patch is usually a patch. What raises the concern level is a combination — a repair that’s newer than the surrounding wear, plus a dimensional mismatch, plus fasteners that don’t match the originals.

The right response to a genuine concern is to stop, not to investigate further yourself. Set the container aside, don’t load it, and escalate to your security contact and CBP.

Frequently asked questions

Is the 7-point inspection legally required?

It’s a requirement of participation in CTPAT and similar supply chain security programs rather than a standalone legal mandate for all shippers. If you’re a CTPAT member, your minimum security criteria include container inspection procedures, and validation visits will look for evidence that they’re followed.

Who performs the container inspection?

Whoever controls the empty container immediately before loading — typically warehouse or CFS staff at the stuffing location. It needs to be someone trained on what to look for, and the inspection has to be documented with the container number, date and inspector.

What’s the difference between a 7-point and a 17-point inspection?

Seven points is the standard for ocean containers. The seventeen-point inspection applies to trailers and adds checks specific to tractor and trailer components such as the refrigeration unit, fifth wheel, tires, and fuel tanks.