What Is Transport Security Packaging? (Tamper Seals)
Transport security packaging combines a package or container, a single-use tamper seal, and a custody record. The seal makes some forms of unauthorized opening easier to detect; it does not prove that the contents stayed secure. Choose the right standard and seal for the route, fit it to the locking point, record its ID, and check it at each handoff.
A seal can offer reassurance, but only if the people receiving a shipment can tell whether it is the same seal that left the sender. That means a strong-looking device alone is not enough. The seal, the way it fits, and the records around it all matter.
I use a simple test when planning a shipment: could a receiver identify the seal, compare it with the handoff record, and spot signs of interference before opening the package? If the answer is no, the process needs work.
What is transport security packaging?
Transport security packaging is a package or freight container closed in a way that makes unauthorized access detectable during transit. A tamper seal is a single-use device fitted at a closure point. Its unique identifier and the custody record help people compare what was applied with what arrives.
The word “security” can sound absolute, but a seal is not a guarantee. It may show signs of cutting, replacement, or damage. An intact seal does not prove that no one accessed the shipment by another route, or that the contents were correct when packed.
A sound system links four parts:
- A package or container suited to the goods and journey
- A closure point that the seal can secure
- A seal selected for the required standard and threat
- A record that ties the seal’s identifier to a handoff
This is why transport security packaging means more than attaching a numbered tag. The seal needs to fit, and each person who accepts custody needs a clear way to check it.
Planning: Select the Applicable Seal Standard and Threat Level
Start by identifying the package, route, likely threats, and receiver’s requirements. Then choose the applicable standard and seal class. Standards serve distinct purposes, so do not select a seal by appearance alone or assume one standard governs every package.
For mechanical freight-container seals, ISO 17712:2013 defines three classes: indicative, security, and high-security. The receiving party, carrier, contract, and route may set additional requirements. Check those before ordering, since a seal that meets one need may not meet another.
| ISO 17712 class | General use | Mechanical strength threshold noted in the standard criteria |
|---|---|---|
| Indicative | Shows evidence of interference; lower level of physical resistance | No threshold stated here |
| Security | Greater resistance than an indicative seal | 1 kN tensile strength |
| High-security | Higher mechanical resistance for freight-container use | 10 kN tensile strength |
The tensile values are test criteria for seals. They are not cargo load limits, and they do not guarantee resistance to every tool or attack method. A higher class also does not replace inspection or recordkeeping.
For medicinal products, a separate rule may apply. Under 21 CFR 211.132, covered over-the-counter human drug products sold at retail must meet tamper-evident packaging requirements. This is not a general rule for freight seals. A high-security container seal does not, by itself, meet a product-package tamper-evidence requirement.
ASTM D4169 offers a framework for evaluating shipping containers and systems under distribution cycles. It does not certify a tamper seal or replace the applicable seal-class requirements. Use it when assessing distribution performance, not as proof that a seal meets ISO 17712.
Next step: Write down the required standard, class, route, and receiver’s acceptance criteria before selecting a product.
How do the seal classes compare?
A seal class describes a level of mechanical performance or indication under the applicable standard. It does not describe every feature of a shipment’s security plan. Match the class to the threat and contract, then verify the seal and custody process separately.
Indicative seals can help reveal opening or substitution, but they provide less mechanical resistance than security or high-security classes. High-security seals are designed for freight-container use where greater strength is needed. The correct choice depends on the shipment and the receiving party’s rules, not on the idea that “stronger is always sufficient.”
Access and Fit: Check the Locking Interface Before Selection
The locking interface is the hasp, latch, or other point through which the seal is installed. Check its shape, access, and condition before ordering seals. ISO 17712 does not set one universal bolt diameter, seal length, or locking-interface clearance, so fit must be confirmed for the specific closure.
A seal must pass through the intended locking point and engage as designed. It should not be possible to remove it without visible damage or changing its identifier. Do not force a seal into a misaligned, worn, or obstructed hasp; correct the closure or select a compatible seal.
Before purchase, compare the manufacturer’s dimensions with the actual locking point. Confirm:
- The seal can be applied after the package or container is fully closed.
- The locking point does not leave an easy path for removal or substitution.
- The seal does not interfere with normal transport or handling.
- The receiver can inspect the seal and read its identifier.
- The seal type and class meet the applicable contract or rule.
If the closure has several locking points, follow the carrier or customer’s instructions on which points require sealing. Adding seals without a plan can make inspection confusing. A clear, repeatable seal location is easier to document and check.
Execution: Apply the Seal and Maintain Custody Records
Apply a new, single-use seal only after the package or container is fully closed. Install it through the intended locking point, check that it is engaged, and record its unique identifier at handoff. Every later custody transfer should compare the seal with that record.
Use a consistent sequence:
- Survey: Identify the package type, locking point, route, threat level, and receiver requirements.
- Specify: Select a compatible single-use seal and required standard or class. Decide how the ID will be recorded and checked.
- Apply: Close the package fully, install the seal as directed, and confirm it is engaged.
- Record: Write down the seal identifier and link it to the shipment and handoff.
- Transfer: Have the receiving party compare the physical seal with the record before opening.
- Resolve: Record and report any mismatch or damage before the shipment is opened, unless safety or an applicable procedure requires otherwise.
Never reuse a one-time seal. Do not accept an identifier that is missing from the record or does not match it. If the seal is damaged before departure, replace it and update the record; do not leave the old ID as the active seal number.
What should a custody record include?
A custody record links a seal to a shipment and to the people who transfer it. Keep the fields clear enough that another person can check the shipment without guessing. A complete record helps show what was applied and what was observed at each handoff.
| Record field | Example of what to capture |
|---|---|
| Shipment reference | Order, load, or container number |
| Seal identifier | The full printed or marked ID |
| Application | Date, time, and location |
| Handoff | Releasing and receiving parties |
| Inspection | ID match, visible condition, and any concern |
| Exception | What differed, when found, and who was notified |
A photograph may support the record if the relevant parties permit it, but it does not replace the written identifier and inspection. Keep records according to the contract, business procedure, or applicable rules.
Verification: Inspect Identifiers, Seal Condition, and Exceptions
At each custody transfer, compare the seal’s identifier with the record before opening. Inspect for cuts, substitution, deformation, or disturbance around the locking point. An intact seal is evidence to consider, not proof that the contents were untouched or correct.
Check the full identifier, not just its last few digits. Look for signs that the seal has been cut or altered, that its parts have shifted, or that the closure itself is damaged. If the ID does not match, treat the difference as an exception even when the seal looks undamaged.
Document what you see before opening when practical. Follow the carrier’s reporting steps and notify the responsible party. Do not describe a seal as “tamper-proof,” and do not treat a seal check as a substitute for checking the shipment contents.
Illustrative receiving scenarios
These examples are process scenarios, not reported case studies. They show how the same inspection steps apply to different shipments and where a seal alone has limits.
Container seal matches: A receiver checks the full ID against the dispatch record and sees no obvious damage. The match supports the custody record, but it does not prove the load’s contents or rule out access through another route. The receiver should still follow normal cargo checks.
ID mismatch: A seal appears intact, but its number differs from the recorded number. The receiver should pause opening when practical, document the mismatch, and report it through the agreed process. Appearance alone does not resolve the record conflict.
Retail drug package: A high-security freight seal is present on the transport container, but the package-level tamper-evident feature for a covered OTC drug product must still be assessed separately under 21 CFR 211.132. The container seal does not replace that requirement.
Conclusion: Build a Checkable Seal Process
A useful transport seal system makes interference easier to detect and gives each handoff a record to check. Select the standard that applies, confirm the physical fit, use a new seal, and document its identifier. Then inspect the seal and record together at every transfer.
Choose the seal for the shipment and receiving requirements, not for appearance or strength alone. If an identifier or condition raises doubt, record the exception and follow the agreed response before treating the shipment as verified.
Frequently Asked Questions
These answers summarize the core distinctions between transport seals, standards, and inspection. They are general guidance; contracts, carrier rules, and product-specific regulations may set additional requirements. Confirm the applicable terms before shipping or accepting a regulated product.
What is a tamper seal used for in transport?
It helps make unauthorized opening or replacement detectable and links the closure to a custody record.
Does an intact seal prove the contents are secure?
No. It records the condition of the seal at inspection, not everything that happened to the contents.
What does ISO 17712 cover?
ISO 17712:2013 sets requirements for mechanical freight-container seals and defines indicative, security, and high-security classes.
What is the difference between security and high-security seals?
They are different ISO 17712 classes. The stated tensile thresholds are 1 kN for security and 10 kN for high-security seals.
Does ISO 17712 set one standard bolt size?
No. It does not establish one universal bolt diameter, seal length, or clearance. Check the seal against the actual locking point.
Can I reuse a single-use tamper seal?
No. Replace it with a new seal and record the new identifier.
Does ASTM D4169 certify a tamper seal?
No. It provides a distribution-cycle performance framework for shipping containers and systems; it does not certify a seal.
Does a freight-container seal satisfy OTC drug packaging rules?
Not by itself. Covered OTC human drug products sold at retail may be subject to 21 CFR 211.132 package-level tamper-evidence requirements.
What should I do if the seal ID does not match the record?
Document the mismatch, notify the responsible party, and follow the agreed exception process before opening when practical.
What should be recorded when applying a seal?
Record the shipment reference, full seal ID, application time and place, and the handoff details needed for later checks.
(This article was written by one of our staff writers, Garrett Vance. Visit our Meet the Team page.)
