UN38.3 and IATA: How to Ship Lithium Battery Wellness Products by Air Without Problems

Why Lithium Batteries Are Regulated as Dangerous Goods

Lithium-ion batteries power the vast majority of modern personal wellness devices — vibrators, wearables, couples' tech, app-connected intimate devices. They are energy-dense, compact, and rechargeable. They are also capable of thermal runaway: a chain reaction where a damaged or defective cell overheats, vents flammable electrolyte, and can ignite. At altitude in a cargo hold, a battery fire is catastrophic.

The aviation industry began regulating lithium batteries as dangerous goods (DG) after a series of cargo aircraft fires in the 2000s and 2010s, including events later attributed to lithium battery shipments. The International Air Transport Association (IATA) codified the requirements in its Dangerous Goods Regulations (DGR), which are updated annually and are binding on all IATA member airlines — which is essentially every commercial airline operating internationally.

UN38.3 is the United Nations test standard (from the UN Manual of Tests and Criteria, Part III, Section 38.3) that lithium cells and batteries must pass to demonstrate they can be safely transported. The tests simulate the conditions batteries encounter in transport: altitude simulation, thermal testing, vibration, shock, external short circuit, impact, overcharge, and forced discharge. Batteries that pass all tests receive a UN38.3 test summary — the fundamental document your freight forwarder and airline require.

For wellness product brands, the practical reality is this: if your product has a lithium battery (which it almost certainly does), shipping it by air — whether via express courier or air freight — requires UN38.3 test documentation and compliance with IATA DGR packing instructions. Attempting to ship non-compliant lithium battery products by air risks shipment refusal, seizure by customs, and significant fines. Airlines and couriers refuse non-compliant shipments and ban repeat offenders.

Understanding UN38.3: What the Test Covers

UN38.3 testing consists of eight individual tests performed on cells and batteries intended for transport. Understanding what is tested helps you ask the right questions of your OEM and verify that test reports are genuine.

Test T.1 — Altitude simulation: The battery is stored at a simulated altitude of 15,000 meters (low pressure) for six hours. This tests the battery's resistance to leakage or rupture that could occur in unpressurized cargo holds.

Test T.2 — Thermal test: The battery undergoes rapid temperature cycling between -40°C and +75°C, with storage periods at each extreme. This tests sealing integrity and the battery's resistance to temperature-induced stress.

Test T.3 — Vibration: The battery is subjected to sinusoidal vibration spanning 7–200 Hz frequencies. This simulates the vibration experienced in transport vehicles.

Test T.4 — Shock: The battery undergoes mechanical shock testing — half-sine pulses of 150 g for cells or 50 g for batteries — to test structural integrity.

Test T.5 — External short circuit: The battery's terminals are short-circuited and the battery is monitored for thermal runaway, fire, or explosion.

Test T.6 — Impact: A 9.1 kg bar is dropped onto the battery from a height of 61 cm. This tests the battery's behavior under physical impact.

Test T.7 — Overcharge: The battery is charged at twice its maximum charge voltage for 24 hours. This tests the protection circuitry.

Test T.8 — Forced discharge: The battery is discharged below its minimum voltage. This tests behavior under over-discharge conditions.

All eight tests must be passed for the battery to be UN38.3 compliant. The test report must identify the specific cell or battery model tested, the test lab, and the results for each test. Your OEM should be able to provide the UN38.3 test summary as part of their standard compliance documentation package for any product with a lithium battery.

IATA Packing Instructions: PI 965, PI 966, PI 967

IATA DGR assigns lithium battery shipments to specific packing instructions depending on what is being shipped. The three relevant packing instructions for wellness product brands are:

PI 965 — Lithium ion cells and batteries shipped alone (not installed in or packed with equipment): This applies when you are shipping bare battery packs or cells without the device. This scenario is uncommon for finished wellness products but relevant if you are shipping replacement batteries or battery modules separately. PI 965 has the most restrictive requirements, including an absolute prohibition on passenger aircraft for Section IB (large batteries >100Wh) and strict quantity limits.

PI 966 — Lithium ion batteries packed with equipment: This applies when batteries (not installed in the device) are shipped in the same package as the device — for example, spare batteries included as accessories. Most finished wellness products with spare or replacement batteries fall here.

PI 967 — Lithium ion batteries installed in equipment: This is the most common classification for finished wellness products. The battery is already installed in the device at time of shipment. PI 967 is the least restrictive of the three for small devices and permits shipment on passenger aircraft subject to watt-hour limits.

Within each packing instruction, batteries are further divided into Section I (larger batteries, more restrictions) and Section II (smaller batteries, less restrictive, typically applicable to most consumer wellness devices with batteries under 100Wh per cell and 160Wh aggregate).

For most adult wellness products: A vibrator with a single lithium-ion cell of 400–800mAh at 3.7V has a watt-hour rating of approximately 1.5–3.0 Wh. This is far below the 100Wh threshold for Section II of PI 967, making it eligible for passenger aircraft with relatively straightforward documentation requirements.

State of Charge Requirements

State of charge (SOC) requirements are one of the most operationally significant IATA DGR rules for wellness product brands shipping by air. SOC restrictions limit how fully charged a lithium battery can be at time of shipment.

For cargo aircraft (freighter flights): IATA DGR Section II of PI 965 and PI 966 requires that cells and batteries are shipped at no more than 30% of rated capacity. This means your OEM must discharge batteries to 30% SOC before boxing finished products for air freight shipment. This applies to bare cells and batteries packed with equipment shipped as cargo.

For passenger aircraft (PI 967 — installed in equipment): Batteries installed in equipment (finished devices) shipped as cargo on passenger aircraft do not have a SOC restriction under PI 967 Section II. The device can ship fully charged. However, individual airlines may impose more restrictive policies — always verify with your freight forwarder.

For express courier shipments (DHL, FedEx, UPS): Express couriers use a mix of passenger and cargo aircraft depending on route. Their published dangerous goods guidelines typically require SOC ≤30% for shipments classified under PI 965 or PI 966 Section II. Finished product shipments under PI 967 Section II (batteries in equipment, ≤100Wh) generally have no SOC requirement from the couriers, but this varies by route and is subject to change.

Practical implications for OEM production: If your products are shipping by air cargo (not installed-in-equipment express courier), your OEM must include a battery discharge step in the production process. This adds time to the production timeline — batteries must be discharged to 30%, then the packaging process cannot re-charge them. Discuss this with your OEM production manager and freight forwarder before finalizing shipping arrangements.

Watt-Hour Limits by Transport Mode

Watt-hour (Wh) rating is the key metric that determines which section of a packing instruction applies to your shipment and whether your batteries can travel on passenger aircraft. Watt-hour rating = nominal voltage × capacity in amp-hours.

For a typical wellness device with a 3.7V, 500mAh battery: 3.7V × 0.5Ah = 1.85 Wh. This is well within all relevant thresholds.

For a high-capacity wearable with two cells — 3.7V × 2,000mAh each: 3.7 × 2.0 = 7.4 Wh per cell, 14.8 Wh aggregate. Still within Section II thresholds.

For approval on cargo aircraft for large batteries: Shipments exceeding PI 967 Section I limits require approval from the State of Origin, the State of the Operator, and all States to be overflown. This is an intensive process that typically takes weeks and involves airline-specific dangerous goods approvals. It is not relevant for standard wellness device products, which are far below these thresholds.

Why this matters for bulk shipments: Even if individual units are within Section II limits, large pallet quantities require correct outer carton labeling (lithium battery mark, class 9 hazard label, and handling labels). Your OEM must apply these labels correctly before export. A container of 10,000 wellness devices that arrives at the freight terminal with incorrect or missing lithium battery marks will be held pending re-labeling — at your expense.

Shipping Documents You Need

Shipping lithium battery products by air requires a set of documents beyond the standard commercial invoice and packing list. Missing or incorrect documents are the most common reason freight forwarders refuse to book DG shipments.

UN38.3 Test Summary: The fundamental document proving your battery has passed the UN transport test. This is issued by the test laboratory. It must identify the specific cell/battery model, the testing organization, and confirm passage of all eight tests. Your OEM holds this document — request it as part of your compliance documentation package.

Shipper's Declaration for Dangerous Goods: Formally called the "Shipper's Declaration for Dangerous Goods" (IATA DGR Form), this is completed by the shipper (you or your OEM, acting as shipper) and submitted to the freight forwarder or airline. It must be completed in English, use prescribed UN dangerous goods descriptions, and be signed by a person trained in IATA DGR. Many OEM factories in China have DG-trained logistics staff who can complete this form. If yours does not, use a DG-experienced freight forwarder.

The Shipper's Declaration is NOT required for PI 967 Section II (finished products with batteries in equipment, ≤100Wh) shipped by express courier under the courier's own dangerous goods program. However, the shipper must still provide a written notification to the operator (typically a checkbox or declaration in the courier's booking system) that the shipment contains lithium batteries.

Material Safety Data Sheet (SDS/MSDS): Required by some carriers and customs authorities. The SDS for a lithium-ion battery covers the hazardous properties of the battery's components (lithium salts, organic electrolytes) and emergency response procedures.

Package certification: For Section II shipments under PI 967, the package itself must meet IATA DGR standards. Your OEM's packaging must be strong enough to prevent accidental operation of the device (which could generate heat) and must carry the lithium battery mark and the operator's warning label.

Courier-Specific Rules: DHL, FedEx, UPS

The three major international express couriers — DHL, FedEx, and UPS — operate their own dangerous goods programs that implement IATA DGR but add courier-specific rules. Understanding the differences prevents surprises at collection.

DHL: DHL Express accepts lithium batteries in equipment (PI 967 Section II) on most routes without a Shipper's Declaration for shipments under 100Wh aggregate. The shipper must declare the contents in the DHL Express waybill (select "Lithium batteries in equipment" from the dangerous goods options). DHL has a separate "Special Delivery" program for dangerous goods requiring a Shipper's Declaration (Sections I). Not all DHL service points are equipped to handle DG shipments — consignment must be booked and dropped off at DHL DG-capable service centers.

FedEx: FedEx International Priority and Economy accept lithium batteries in equipment (PI 967 Section II) on most routes. FedEx requires the shipper to complete FedEx's Lithium Battery Certification on the waybill. FedEx has periodic route-specific restrictions — certain destinations in the Middle East and Africa have additional requirements. FedEx's DG acceptance guide (updated quarterly) is the definitive reference.

UPS: UPS accepts PI 967 Section II shipments on most international routes with online declaration during booking. UPS applies per-package quantity limits: up to 2 kg of lithium-ion batteries per package for Section II. UPS also requires that the lithium battery mark (UN3481 for batteries in equipment) is applied to the outer carton.

Comparison of key courier requirements:

If a courier refuses your shipment, ask specifically which requirement the shipment fails. Common refusal reasons: missing lithium battery mark on outer carton, undeclared DG content, SOC too high for route requirements, or missing UN38.3 documentation for batteries exceeding standard Section II thresholds.

Outer Carton Labeling Requirements

Correct labeling of outer cartons is a physical compliance requirement that your OEM must apply before the shipment leaves China. Incorrect or missing labels are a leading cause of shipment hold-ups at export customs and airline acceptance.

Lithium battery mark: A rectangular mark with the UN number (UN3480 for lithium-ion batteries alone, UN3481 for lithium-ion batteries in or with equipment). The mark must be at least 120mm wide × 110mm tall. The mark includes the battery illustration, UN number, and shipper/consignee contact information fields. This mark is required on all outer packages containing lithium batteries, regardless of packing instruction section.

Class 9 hazard label: For Section I shipments (larger batteries), a Class 9 miscellaneous hazardous materials diamond label is required in addition to the lithium battery mark. Section II shipments do not require the Class 9 diamond.

"THIS SIDE UP" arrows: Required on packages containing batteries to indicate correct orientation during transport.

Overpack label: If multiple packages are combined into an overpack (a single outer container holding multiple packages for shipping efficiency), the overpack must be labeled "OVERPACK" and must display the hazard marks visible on the individual packages inside, unless the inner package marks are visible through the overpack.

Package orientation arrows: When devices are packaged with the battery installed in a specific orientation relative to shipping, orientation arrows prevent the battery from being stored upside down — a concern for liquid electrolyte cells.

Your OEM's export packaging team should be familiar with these requirements. Request to review a physical sample of the export carton labels before approving the production run. A photograph of the labeled carton is sufficient for remote review. Catching a labeling error before 500 cartons are packed saves significant rework cost.

What to Do When a Courier Refuses Your Shipment

Courier refusals are more common than most brands expect on their first few international DG shipments. The refusal is rarely arbitrary — it is based on a specific gap between the shipment's documentation or labeling and the courier's requirements. Knowing how to diagnose and resolve the issue quickly minimizes delay.

Step 1 — Get the specific reason in writing: Ask the courier's dangerous goods desk (not the regular customer service line) to provide the specific regulation or requirement the shipment fails to meet. General refusals ("your shipment contains dangerous goods we cannot accept") must be followed up with specifics before you can correct the issue.

Common refusal reasons and remedies:

• Missing lithium battery mark: OEM must apply the correct mark to outer cartons. Ship the labels to the OEM or arrange re-labeling at a local warehouse.
• Undeclared lithium batteries: Shipper failed to declare DG content at booking. Cancel and rebook with correct DG declaration.
• SOC too high: Battery discharged insufficiently. Requires OEM to discharge to compliant SOC before repackaging.
• Missing UN38.3 summary: Request from OEM immediately. If OEM cannot produce it, the battery has not been properly tested — escalate to your OEM account manager as a compliance issue, not a logistics issue.
• Watt-hour limit exceeded for route: Reroute via sea freight or find an airline that accepts the higher-capacity battery under an approved dangerous goods program.

When no courier will accept your shipment by air: Sea freight does not have the same lithium battery restrictions as air freight. While slower, sea freight is the correct mode for large battery banks (>100Wh per battery) or for situations where air freight documentation cannot be resolved quickly. Build sea freight into your logistics planning as a fallback for new product launches.