Dangerous Goods Testing: UN Classification, Lithium Battery & Packaging Tests

If you are shipping lithium batteries, industrial chemicals, or any product that falls under the UN Class 9 miscellaneous dangerous goods designation, you cannot legally move cargo across international borders without first completing the appropriate Dangerous Goods Testing. This page walks you through the UN classification framework, the specific test sequences required for lithium cells and batteries (UN 38.3), the mandatory packaging performance trials (drop, stack, leak, vibration), and the certification process that competent authorities and authorized test labs follow. By the end, you will know exactly which tests apply to your product, what the pass/fail criteria are, and how to secure a UN certificate for dangerous goods that carriers and customs will accept.

Dangerous Goods Testing is not a single test – it is a layered system of classification procedures, physical performance trials, and documentation requirements all rooted in the United Nations Recommendations on the Transport of Dangerous Goods, Model Regulations. The UN Manual of Tests and Criteria, currently in its eighth revised edition with Amendment 1 adopted in September 2025, provides the test methods and criteria that competent authorities and designated laboratories use to determine the proper classification and packaging level for any dangerous good . Whether you are shipping a pallet of lithium-ion power banks by air or a container of corrosive liquids by sea, the same foundational question applies: has your product and its packaging passed the required Dangerous Goods Testing for its assigned hazard class and packing group?

This article covers three interconnected areas that every DG manufacturer and lithium battery exporter must master. First, the UN classification system and how it determines which tests apply. Second, the eight-test UN 38.3 sequence for lithium metal and lithium-ion cells and batteries – the most frequently encountered Dangerous Goods Testing requirement for electronics and energy storage exporters. Third, the packaging performance tests (drop, stacking, leakproofness, vibration, and hydrostatic pressure) that every outer package must pass to earn a UN mark. We also explain the certification process, including how to work with an authorized test lab, what a UN certificate for dangerous goods actually contains, and how often you need to renew.

Bottom line: Dangerous Goods Testing is mandatory, mode-specific, and strictly enforced. Without a valid test summary or packaging certificate, your shipment will be rejected at the port or airport. This page gives you the regulatory framework, the test parameters, and the practical steps to get your products certified – so you can ship with confidence. [source: www.greathensen.com]

What Is Dangerous Goods Testing? The UN Classification Framework and When It Applies

Dangerous Goods Testing is the formal process of subjecting a substance, article, or its packaging to a defined set of physical, chemical, and thermal trials to determine its hazard class, packing group, and transport eligibility. The framework originates from the United Nations Recommendations on the Transport of Dangerous Goods, Model Regulations – commonly called the UN Model Regulations – and the detailed test methods are codified in the UN Manual of Tests and Criteria. The current reference edition is the eighth revised edition, published in 2023, with Amendment 1 adopted in September 2025. National and international modal regulations – IATA Dangerous Goods Regulations for air, the IMDG Code for sea, ADR and RID for European road and rail, and the US federal hazmat regulations under 49 CFR Parts 171–180 – all incorporate these UN test standards by reference.

The classification process begins before any test is run. The consignor must properly identify the product's identity, physical state, and known hazardous properties. The UN Model Regulations divide dangerous goods into nine classes, ranging from explosives (Class 1) through gases (Class 2), flammable liquids (Class 3), flammable solids (Class 4), oxidizing substances (Class 5), toxic and infectious substances (Class 6), radioactive material (Class 7), corrosives (Class 8), and miscellaneous dangerous goods (Class 9). Within each class, substances are further assigned to packing groups (PG) I, II, or III, indicating high, medium, or low danger, respectively. The packing group assignment directly determines the stringency of packaging performance requirements – PG I requires the most robust packaging, PG III the least.

The Manual of Tests and Criteria is divided into five parts:

• Part I – Classification procedures, test methods, and criteria relating to explosives.
• Part II – Self-reactive substances, organic peroxides, and polymerizing substances.
• Part III – Aerosols, desensitized explosives (transport only), flammable liquids and solids, pyrophoric substances, substances that emit flammable gases in contact with water, oxidizing substances, corrosive substances, and Class 9 materials – including lithium metal and lithium-ion batteries and solid ammonium nitrate-based fertilizers.
• Part IV – Test methods concerning transport equipment.
• Part V – Classification procedures, test methods, and criteria relating to sectors other than transport.

For most DG manufacturers and lithium battery exporters, the relevant tests fall under Part III, specifically Sub-section 38.3 for lithium batteries (the UN 38.3 test regime), and the packaging performance tests described in the various sections of Part III that apply to the specific hazard class. The Manual also includes appendices covering national contacts for test details, emergency relief vent sizing for portable tanks, screening procedures, and test methods for fireworks classification.

The default position under the UN system is that classification requires testing unless a specific entry or special provision explicitly waives the requirement. For well-characterized substances with established UN entries, historical data may allow classification without fresh testing, but for new formulations, product variants, or any change in manufacturing process or component sourcing, new Dangerous Goods Testing is generally required. Testing is not optional for lithium batteries of any chemistry – every lithium metal or lithium-ion cell or battery shipped internationally, whether standalone or contained in equipment, must pass the UN 38.3 test sequence.

The table below summarizes the UN hazard classes most frequently encountered by DG manufacturers and lithium battery exporters, the typical tests required, and the applicable sections of the Manual of Tests and Criteria. Note that this is a representative summary – the actual test regimen depends on the specific UN number and the physical and chemical properties of the substance.

Every test result must be documented in a test report issued by a laboratory recognized by the competent authority of the country of origin. For lithium batteries, the test report is summarized in a UN 38.3 test summary that must be available to carriers, freight forwarders, and competent authorities upon request. [source: iata.org] For packaging, the test report underpins the UN mark that must be printed on the outer packaging – without that mark, the packaging is not legally authorized for transport of dangerous goods.

In practice, the classification and testing workflow follows this sequence:

1. Identify the product – proper shipping name, UN number, physical state, known hazards.
2. Consult the UN Model Regulations – determine the likely hazard class and packing group.
3. Select the applicable test methods – from the Manual of Tests and Criteria.
4. Engage an authorized test lab – submit samples for testing.
5. Obtain the test report and certificate – for lithium batteries, the UN 38.3 test summary; for packaging, the test report supporting the UN mark. [source: iata.org]
6. Maintain documentation – test summaries and certificates must be kept on file and provided to carriers on request.

The entire classification and Dangerous Goods Testing process is the legal responsibility of the consignor. Carriers, freight forwarders, and competent authorities all rely on the test documentation to verify compliance. Without valid Dangerous Goods Testing, your shipment will not be accepted for transport – and if discovered in transit, it may be detained, returned, or destroyed at your expense.

Required Dangerous Goods Tests: UN 38.3, Drop, Stack, Leak, and Vibration by DG Class

Once the hazard classification is established, the next step is executing the specific test sequences that apply to your product and its packaging. The most common Dangerous Goods Testing requirements fall into two broad categories: product tests (which determine the intrinsic hazard of the substance or article) and packaging performance tests (which verify that the packaging can contain the dangerous good safely during normal transport conditions). For lithium batteries, these two categories converge in the UN 38.3 test sequence – a dedicated eight-test regime that applies to all lithium metal and lithium-ion cells and batteries, regardless of size or energy capacity.

UN 38.3 – The Lithium Battery Test Regime

UN 38.3 is the most frequently encountered Dangerous Goods Testing requirement for exporters of portable electronics, power tools, energy storage systems, and electric vehicle batteries. The test sequence is prescribed in Sub-section 38.3 of the UN Manual of Tests and Criteria and comprises eight distinct tests, designated T.1 through T.8. Each test addresses a specific failure mode or transport hazard.

Each test in the UN 38.3 sequence must be performed on new cells or batteries in the same state as offered for transport. The test samples must be representative of the production lot, and the test report must include detailed descriptions of the cell/battery design, construction, and materials. For batteries assembled from multiple cells, the tests are typically performed on the battery as a whole, though some competent authorities may accept cell-level testing for certain battery designs.

The UN 38.3 test summary – the document that certifies compliance – must be issued by a laboratory recognized by the competent authority of the country of manufacture. The test summary must be made available to carriers and competent authorities upon request, and it remains valid as long as there is no change in the cell/battery design, materials, or manufacturing process. Any significant change – even a change in the electrolyte formulation or the separator material – requires retesting. The test summary must include the following minimum information: cell/battery identification, test laboratory name and address, report number, test dates, a list of all tests performed, and a statement of compliance.

For large-format batteries used in electric vehicles and energy storage systems, the UN 38.3 test sequence is often conducted on a representative sub-assembly or on the complete battery system, depending on the size and the test lab's capabilities. Some competent authorities allow the use of cell-level testing for batteries that are assembled from cells that have already passed UN 38.3, provided the battery design does not introduce new failure modes. However, this is not universally accepted – many carriers and regulators require battery-level testing for any battery exceeding a certain energy threshold.

Packaging Performance Tests – Drop, Stack, Leak, Vibration, and Hydrostatic Pressure

For all dangerous goods transported in packaging, the packaging itself must pass a series of performance tests that simulate the mechanical stresses encountered during normal transport. The test requirements are specified in the UN Model Regulations and are mandatory for all packaging that bears a UN mark. The specific tests and their pass/fail criteria depend on the packing group assigned to the dangerous good – PG I (highest danger) requires the most stringent packaging performance, while PG III requires the least.

The drop test is the most widely recognized packaging performance test. The packaging is filled with the dangerous good (or a non-hazardous simulant with the same physical properties) and dropped from a specified height onto a rigid, non-resilient surface. The drop orientation must include the most vulnerable positions – typically the bottom, a side, and the top. For PG I packaging, the drop height is 1.8 meters; for PG II, 1.2 meters; for PG III, 0.8 meters. The packaging must not leak, and for plastics, it must not crack or rupture in a way that would allow leakage.

The stacking test simulates the compressive forces that packaging experiences when stacked in a transport container or warehouse. The packaging is subjected to a compressive load equivalent to a stack height of 3 meters for a period of 24 hours. For packaging containing dangerous goods, the test must be performed at the maximum load that the packaging is designed to carry. The packaging must not show any permanent deformation that would compromise its integrity.

The leakproofness test applies to plastics drums and jerricans that are used to transport liquids. The packaging is pressurized with air to 30 kPa for 5 minutes, and any leakage is detected by pressure drop or by visual inspection of a submerged packaging. The test is performed at the maximum filling temperature and must show no leakage.

The hydrostatic pressure test is another requirement for plastics drums and jerricans. The packaging is filled with water and pressurized to 100 kPa for 5 minutes. The test verifies that the packaging can withstand the internal pressure generated by the liquid contents without leaking.

The vibration test is required for certain transport modes, particularly air transport. The packaging is subjected to sinusoidal vibration at frequencies from 5 Hz to 50 Hz at an acceleration of 0.5 g. The test duration is typically 1 hour per axis, and the packaging must show no damage or leakage.

Test Sequence by DG Class – A Practical Guide

The table below provides a practical guide to the Dangerous Goods Testing requirements for the most common hazard classes encountered by DG manufacturers and lithium battery exporters. Note that this is a summary – the actual test regimen depends on the specific UN number, the physical state of the substance (solid, liquid, gas), and the packaging type.

For lithium batteries, the packaging performance tests apply to the outer packaging that contains the batteries. The outer packaging must be UN-certified for the specific packing group and must bear the appropriate UN mark. The drop test for lithium battery packaging is typically performed at a height of 1.2 meters (PG II) or 0.8 meters (PG III), depending on the packaging design and the competent authority's requirements.

Authorized Test Labs and Competent Authority Recognition

Dangerous Goods Testing must be performed by a laboratory that is recognized by the competent authority of the country of manufacture. In the United States, the competent authority is the Pipeline and Hazardous Materials Safety Administration (PHMSA) under the Department of Transportation. PHMSA does not directly accredit laboratories but relies on third-party accreditation bodies such as the American Association for Laboratory Accreditation (A2LA) or the ANSI National Accreditation Board (ANAB). Laboratories that hold ISO 17025 accreditation for the relevant test methods are typically accepted by PHMSA and by most other competent authorities.

In the European Union, the competent authorities are the national transport ministries of each member state. Laboratories must be designated by the competent authority of the member state in which they are located. In China, the competent authority is the Ministry of Transport, and laboratories must be designated by the China National Accreditation Service for Conformity Assessment (CNAS). In all cases, the test report must be issued by a laboratory that is recognized by the competent authority of the country of manufacture – and that recognition must be current at the time of testing.

When selecting a test lab, DG manufacturers and lithium battery exporters should verify the lab's scope of accreditation – not all ISO 17025 accredited labs are authorized to perform UN 38.3 testing or packaging performance tests. The lab's accreditation certificate should explicitly list the UN test methods (e.g., "UN Manual of Tests and Criteria, Sub-section 38.3" or "UN packaging performance tests"). The lab should also have experience with the specific product type – testing a small cylindrical cell is very different from testing a large-format EV battery, and not all labs have the equipment or expertise to handle large batteries safely.

Certification Process and Authorized Labs: How to Secure Your UN Certificate

Understanding the certification process is just as critical as understanding the tests themselves. A perfect test result has no value if the documentation is incomplete, the laboratory lacks proper recognition, or the certificate expires before your shipment departs. This section walks through the step‑by‑step workflow for obtaining a UN certificate for dangerous goods – covering both lithium battery UN 38.3 test summaries and packaging performance certificates – and explains how to select an authorized test lab that carriers and competent authorities will accept.

The UN 38.3 Certification Workflow for Lithium Batteries

For lithium batteries and cells, the certification process follows a standardized sequence that typically takes 10 to 15 working days for standard battery types, though complex or large‑format batteries may require longer. The workflow generally proceeds as follows:

Step 1: Pre‑testing consultation. Before submitting samples, engage with the test lab to confirm the applicable UN number (UN 3480 for lithium‑ion batteries shipped alone, UN 3481 for batteries contained in equipment, UN 3090 for lithium metal batteries, or UN 3091 for lithium metal contained in equipment). The lab will also advise on sample quantity – typically, UN 38.3 requires five cells and five batteries for the full test sequence, though the exact number depends on the cell type and the lab's specific protocol. Provide the lab with the cell chemistry data sheet, charge/discharge specifications, and any previous test reports if available.

Step 2: Sample submission and test execution. The laboratory receives the samples and runs the eight‑test UN 38.3 sequence – T.1 through T.8 – in the prescribed order. Note that the tests cannot be fully parallelized because some tests share the same sample set; the lab will manage the sequencing to minimize the overall timeline while maintaining test integrity. The lab documents all test conditions, observations, and measurements, and records any failures or anomalies.

Step 3: Test report and test summary issuance. Upon successful completion of all applicable tests, the lab issues a full test report and a UN 38.3 test summary. [source: iata.org] The test summary is the document that shippers must make available to carriers, freight forwarders, customs authorities, and competent authorities upon request. The test summary must include a standardized set of elements that provide traceability and accountability for the tested design type. Under US regulations (49 CFR § 173.185), each manufacturer and subsequent distributor of lithium cells or bithium cells and batteries manufactured after 30 June 2003 must make a UN 38.3 test summary available [source: iata. [source: iata.org]org]. A general statement in a safety data sheet or website does not satisfy this requirement – the shipper must obtain and retain the actual test summary document.

Step 4: Maintain and update documentation. The UN 38.3 test summary remains valid as long as there is no change to the cell or battery design, materials, or manufacturing process. [source: iata.org] Any significant change – a different electrolyte formulation, a new separator material, a change in the anode or cathode chemistry, or even a change in the cell dimensions – requires retesting and a new test summary. The test summary must be kept on file and made available to carriers and competent authorities on request.

The Packaging Certification Workflow for Dangerous Goods

For packaging that will bear a UN mark, the certification process is separate from the product testing and involves a design‑type approval issued by the competent authority of the country where the tests are performed. The workflow for packaging certification is as follows:

Step 1: Select an authorized test station. Packaging performance tests – drop, stack, leakproofness, hydrostatic pressure, and vibration – may only be carried out by authorized test stations that are accredited specifically for UN packaging testing. In the UK, for example, test stations must be accredited by the United Kingdom Accreditation Service (UKAS) in accordance with ISO 17025 and the UK Operational Instructions. In the US, packaging testing for UN certification must be performed by a PHMSA‑approved third‑party certification agency. PHMSA maintains a list of approximately twenty DOT‑approved UN Third Party Certification Agencies that are certified to perform testing of performance‑oriented packagings.

Step 2: Submit packaging samples for testing. The test station subjects specimens of the packaging to the performance tests described in Chapter 6.1 of the UN Model Regulations. The tests are performed on the packaging design type – the specific combination of materials, dimensions, and construction methods that define the packaging. The test samples must be representative of the production lot. If the packaging passes the tests, the packaging design type is regarded as meeting the UN requirements and may be marked accordingly.

Step 3: Apply for the design‑type approval certificate. After successful testing, the test station may apply to the competent authority – for example, the VCA Dangerous Goods Office in the UK or the PHMSA Office of Hazardous Materials Safety in the US – for a design‑type approval certificate and the corresponding UN mark. The application is accompanied by a copy of the test report, which is checked for technical accuracy and content. The competent authority may also request to see specimens of the tested packaging for quality assurance purposes. When all is satisfactory, a package performance certificate is issued.

Step 4: Apply the UN mark and maintain certification. Once the certificate is issued, the packaging manufacturer may apply the UN specification mark to every serially produced packaging that conforms to the design‑type specification. The UN mark must be printed on the packaging and includes the UN symbol, the packaging code, the packing group level, and other identifying information. The certificate holder must pay an annual renewal fee in most jurisdictions – for example, GB certificates are subject to an annual renewal fee, payable in October each year, and any certificate for which the fee remains unpaid by 1 January will be suspended. Additionally, the specification of each packaging design type must be revalidated every 5 years for quality assurance purposes.

How to Select an Authorized Test Lab

Choosing the right test lab is one of the most important decisions in the Dangerous Goods Testing process. A lab with the wrong accreditation, outdated standard capability, or poor industry recognition can delay your shipment, increase costs, and create compliance risks. Based on industry practice and feedback from DG manufacturers and lithium battery exporters, we summarize five core criteria for selecting a reliable test lab:

1. Authoritative accreditation (minimum requirement). The lab must hold ISO/IEC 17025 accreditation for the relevant test methods. For UN 38.3 testing, labs with CNAS (China National Accreditation Service) accreditation are widely recognized under ILAC (International Laboratory Accreditation Cooperation), including by ICAO and IMO. In the US, look for labs accredited by A2LA or ANAB; in the UK, UKAS accreditation is the standard. The lab's accreditation certificate should explicitly list the UN test methods – for example, "UN Manual of Tests and Criteria, Sub‑section 38.3" for lithium batteries or "UN packaging performance tests" for packaging.

2. Up‑to‑date standard capability. UN testing standards evolve. The current reference is the eighth revised edition of the UN Manual of Tests and Criteria, published in 2023, with Amendment 1 adopted in September 2025. The 2023 revision added sodium‑ion batteries to the UN 38.3 scope for the first time. Only labs that are fully updated to the latest standard can confirm compliance. Ask the lab directly: "Are you fully compliant with the eighth revised edition, including Amendment 1?" – and verify their answer against their accreditation scope.

3. Recognition by transport authorities and carriers. A UN 38.3 report must be accepted by airlines and shipping inspectors. Labs that are authorized by major carriers – for example, China Southern Airlines – significantly reduce rejection risks. Similarly, for packaging testing, labs that are recognized by the competent authority of the country of manufacture – such as the VCA Dangerous Goods Office in the UK or PHMSA in the US – are essential.

4. Relevant industry experience. Batteries vary widely – consumer cells, power batteries, energy‑storage systems – and each type presents different testing challenges. Labs with deep experience in your specific product category can better predict risks, provide effective corrective solutions, and shorten retest cycles. For packaging, labs with experience in your packaging material type – fibreboard, plastic, steel – are preferable.

5. One‑stop service capability. UN 38.3 testing is often bundled with other documentation requirements – Safety Data Sheets (SDS), transport test reports, 1.2‑meter drop tests, stacking tests. Labs that offer full‑chain services can save over 20% in time and cost compared to coordinating multiple providers. For packaging, labs that offer design consultation, testing, and certification under one roof streamline the process.

Competent Authority Recognition – A Global Perspective

Competent authority recognition varies by country, but the underlying principle is consistent: the test report must be issued by a laboratory that is recognized by the competent authority of the country where the tests are performed.

In the US, PHMSA grants approvals to companies or individuals who have been evaluated to meet or exceed the safety criteria defined in the Hazardous Materials Regulations (HMR), including the ability to perform package testing as a DOT‑approved Third Party Certificat

Sources and references

• iata.
• iata.org
• www.greathensen.com

All figures verified from public sources; freight rates marked indicative are confirmed at booking.