UN 38.3: what a lithium cell has to pass before it can travel
UN 38.3 is the transport test regime in Section 38.3 of the UN Manual of Tests and Criteria. A lithium cell has to pass eight tests before it can be shipped by air, sea or road, and what the buyer receives is the test summary, not the full report.
| Field | What it says |
|---|---|
| What it is | Section 38.3 of the UN Manual of Tests and Criteria — the transport test regime for lithium cells and batteries |
| Applies to | Lithium-ion and lithium-metal cells and batteries moved by air, sea, road or rail, with limited exceptions |
| Tests | T1 altitude simulation, T2 thermal, T3 vibration, T4 shock, T5 external short circuit, T6 impact or crush, T7 overcharge, T8 forced discharge |
| What the buyer receives | The test summary, which has been required to be made available since 2020 |
| Who issues it | A test laboratory; the cell manufacturer holds the report and passes the summary down the chain |
| What to check | That the model designation on the summary matches the cells being shipped, and that cells and batteries are not treated as the same entry |
Specification basis: the standard text and its current edition. Figures and dates quoted on this page are limited to what each document states, and no certificate is claimed beyond what is held on file.
Why it exists
Lithium cells carry their own oxidiser and their own energy. UN 38.3 is the set of abuse tests that has to be passed before a consignment is accepted for transport at all. It is a transport requirement, not a product quality mark — a cell that passes UN 38.3 is cleared to travel, not guaranteed to perform.
The eight tests
T1 simulates low pressure, T2 cycles the cell through temperature extremes, T3 and T4 apply vibration and mechanical shock, T5 short-circuits the cell externally, T6 applies impact or crush, T7 overcharges it, and T8 forces it into discharge. T7 and T8 apply to cells and batteries respectively in the way the manual sets out for each type.
The practical consequence for a buyer: the tests are destructive and they are run on samples from a production type, not on the cells in your box. That is why the test summary identifies a model, not a batch.
The test summary is the document, not the report
Since 2020 the summary has had to be made available rather than the full laboratory report. It carries the cell and battery designation, the test laboratory, the test date and a statement that the tests were passed.
When a supplier offers "a UN 38.3 certificate", ask for the summary and read the model line. A summary covering a family does not automatically cover a variant added later, and a summary for a battery does not cover the loose cells inside it.
Before you accept a document
How to check it
- Match the model designation, character for character, against the cells being bought.
- Check whether the document covers cells, batteries, or both — they are separate entries.
- Check the date and the issuing laboratory; a summary with no laboratory named is not a test summary.
Questions
UN 38.3 in practice
Is UN 38.3 the same as a safety certification?+
Does a test summary cover a batch?+
Why is the full report not supplied?+
What documentation travels with an order?+
Does a certificate cover every model from that manufacturer?+
Can cells ship by air?+
This page describes how each standard is applied in practice when lithium cells are bought and shipped. It is a summary for procurement, not the standard text itself, and it does not replace your carrier's acceptance check or your own compliance review.
Related
The other standards
Need to know what is held for a model?
Send the designation. The answer is which documents exist, which are on file, and which would have to be obtained.