Oct 11, 2026Testing Standards
IEC 62133-2 vs UN 38.3: Product Safety and Transport Testing Compared
IEC 62133-2 is a portable product-safety standard; UN 38.3 is a transport requirement. Compare scope and decide which testing your battery needs.
Battery datasheets often show IEC 62133-2 and UN 38.3 side by side, which makes the two look like variations of the same approval. They are not. IEC 62133-2 is a product-safety standard: it defines how portable sealed secondary lithium cells and batteries must behave under intended use and reasonably foreseeable misuse. UN 38.3 is a transport-safety test regime: it establishes whether a design may be offered for shipment as dangerous goods. This comparison covers what each standard is for, where each applies, and how to plan testing from your product, use case and markets.
Two standards, two questions
IEC 62133-2 is the IEC safety standard for "portable sealed secondary cells, and batteries made from them, for use in portable applications." The current consolidated edition combines the first edition with its later amendment, which replaced the lithium portion of IEC 62133:2012. Cell-level requirements qualify the electrochemical design; pack-level requirements qualify the integration. It answers a product question: is this battery safe for the user, in the device it is designed for?
UN 38.3 sits in part III, sub-section 38.3 of the UN Manual of Tests and Criteria. Under United States rules, for example, each lithium cell or battery "must be of the type proven to meet the criteria" in 38.3 — regardless of whether the cells inside a battery were already tested. It answers a logistics question: may this design travel, and under what conditions?
Where each one applies
IEC 62133-2 belongs to the product side. It applies to portable applications — products a person carries or handles — and feeds the safety chapter of a certification file that typically supports national market approvals. For industrial or stationary products the standard family shifts: stationary energy storage is addressed by the IEC 62619 family rather than by 62133-2.
UN 38.3 belongs to the movement of goods. Air, sea and road regulations build on the UN Recommendations on the Transport of Dangerous Goods: air through the ICAO Technical Instructions and IATA rules, sea through the IMDG Code, road through ADR, rail through RID. Under air rules, all lithium cell and battery types must have passed the applicable 38.3 tests to be permitted in transport, whether shipped alone, packed with equipment or contained in it. Modes add conditions of their own, such as state-of-charge limits for air shipments. This layer follows the goods, including samples, before anything is sold.
Why they are not interchangeable
The two regimes test different things against different criteria. IEC 62133-2 evaluates a battery as a product component, under use and misuse scenarios relevant to portable equipment. UN 38.3 evaluates a design against transport conditions and classification criteria; its output is permission to ship, not product approval. A 38.3 report does not demonstrate product safety, and a 62133-2 report does not authorize transport. Acceptance chains differ too: product-safety evidence is reviewed by certification bodies and market surveillance authorities, while transport evidence — the battery test summary — is reviewed by carriers, forwarders and regulators.
When a product needs both
Many lithium products need both, and that is the common case. A power bank, a medical device or a power tool pack is a portable product that must meet safety requirements for its markets, and its cells or packs will at some point move as goods — from the cell supplier, through assembly, to the customer.
Both are design-type bodies of evidence, so both are sensitive to change. The UN provisions define when a modification creates a new type: for rechargeable cells, a change of more than 20 percent in watt-hours, a voltage increase of more than 20 percent, or any change that might materially affect the test results — including changes to protection devices, materials, or the number of cells. Product-safety conclusions are similarly tied to a frozen configuration; the laboratory confirms how a specific change affects your existing reports.
How to decide what you need
Is the battery intended for portable use? Product-safety testing anchored on IEC 62133-2, or the standard family that governs your end product, is the starting point.
Is it industrial or stationary? Look at industrial battery standards, such as the IEC 62619 family, rather than the portable-use standard.
Will cells, packs or finished goods be shipped by air, sea or road? UN 38.3 design-type testing and the associated shipping documentation are required, whatever the destination market.
Which markets are you entering? They determine how safety evidence becomes approvals; transport rules follow the modal regulations wherever the goods travel.
For most consumer lithium products the answer is both — run the two programs in parallel so one design freeze serves both.
How LCS supports both programs
LCS tests lithium cells and packs against IEC 62133-2, IEC 62619 and UL 2054, and against UN 38.3, in its battery laboratory in Shenzhen. It covers both sides of the comparison above: product-safety testing for portable and industrial batteries, and transport testing with the test summary shippers ask for. As an IECEE CB Testing Laboratory, LCS supports CB Scheme documentation where that route applies; CB certificates themselves are issued by National Certification Bodies. The laboratory confirms exact sample and document requirements for each project.
If you are unsure which combination applies, send your cell and pack specifications, chemistry, capacity and shipping configuration through the contact page, and our engineers will reply with a test proposal. The Battery Testing service page has more detail on standards, applicable products and the laboratory's process.
FAQs
Can a UN 38.3 report be used as product-safety evidence?
No. UN 38.3 addresses transport classification, not product safety. Market approvals for portable lithium products generally rely on safety evidence such as an IEC 62133-2-based report; your certification body confirms what it accepts for a given market.
If our battery passed IEC 62133-2, can we ship it?
Not by itself. Transport is a separate requirement: lithium cell and battery shipments are expected to carry 38.3-based design-type evidence and the battery test summary, which IEC 62133-2 testing does not replace.
Our batteries travel inside finished equipment. Does UN 38.3 still apply?
In general, yes. The packaging configuration changes how the shipment is classified — contained in or packed with equipment — but the design-type testing applies to the cells and batteries, and the test summary follows them; button cells installed in equipment are the common exception. Your carrier confirms the exact documents for each shipment.
Which one should we do first?
Start both from the design freeze. Transport testing is often needed earliest, because sample shipments are already regulated; product-safety evidence is needed when you apply for market approvals. The sequence depends on your product, use case and markets; the laboratory can help you plan it.
