In this guide, we walk you through the essentials every shipper should understand before preparing hazardous cargo for export. You’ll learn what UN-certified materials are required, and how to ensure your goods meet international packing standards for shipments from China.
Table of Contents:
Why dangerous goods packaging matters more than you think
When shipping dangerous goods from China, most shippers focus on:
- Which carrier will accept my goods?
- How do I fill in the MSDS, DGD, or battery test reports?
- What are the flight or vessel restrictions?
However, carriers don’t even consider acceptance until they check your packaging.
Dangerous goods packaging is not just a box or drum. It’s a system designed to protect:
- People (warehouse teams, handlers, drivers)
- Equipment (aircraft, containers, vehicles)
- The environment
- Your shipment’s transit success
When packaging is incorrect, even by a small detail, your cargo is likely to face:
- DG acceptance failure at origin
- Repacking costs at the airport or terminal
- Shipment rollovers
- Extra storage days
- Higher risk classifications (which increase freight cost)
- Fines or penalties
- Cargo returned to the supplier
Common mistakes exporters make
We see these issues almost every week with shipments leaving China:
- Using strong-looking boxes that are not UN-certified
- Choosing inner bottles that do not match the chemical properties
- Skipping closure instructions
- Applying DG labels incorrectly
- Buying packaging online without checking certification
- Assuming, “My factory always ships this way, so it must be fine.”
In short, when your packaging fails, your shipment fails, no matter how perfect your documents are. At ASLG, we secure your DG packaging so your shipment clears acceptance the first time.
What counts as dangerous goods packaging?
Dangerous goods packaging is not a single item; it’s the entire protective system built around your hazardous materials.
It includes several critical components:
1. Primary packaging
It is the immediate container holding the substance, such as:
- Glass or plastic bottles
- Metal cans or cartridges
- Inner drums
- Cells or battery packs
The primary container must be chemically compatible with the product.
2. Secondary packaging
The outer container protects the inner packaging and absorbs external impact. Common options include:
- UN cartons
- Fiberboard boxes
- Plastic or steel drums
- IBCs
- Aluminum or steel cases
- Pails or jerricans
3. Cushioning and absorbent materials
These materials prevent leaks, breakage, or chemical reactions, especially important for liquids:
- Vermiculite
- Absorbent pads
- Foam inserts
- Clamping or bracing materials
4. Closures
Often overlooked but crucial. Caps, plugs, locking mechanisms, and seals must match the exact UN packaging test report.
5. Labels and markings
Packaging must include correct labels:
- Hazard labels
- Orientation arrows
- UN number markings
- Limited quantity labels
- Excepted quantities label class 3 (when applicable)
- Handling labels
Even if the packaging itself is correct, misplaced or missing labels can lead to DG rejection.
UN-certified packaging explained simply
The term “UN certified packaging for dangerous goods” is widely used but often misunderstood.
What does UN packaging mean?
It means the packaging has passed the strict performance test required by the United Nations. These tests ensure the packaging can withstand:
- Pressure
- Drop impact
- Vibration
- Stacking weight
- Leakproofness (for liquids)
A compliant box or drum carries a UN code such as:
“4G/X13/S/23/CN/XYZ”
Each part of the code has a specific meaning:
- 4G= type of packaging (fiberboard box)
- X = packing group level approved (PG I = highest danger)
- 13= maximum gross weight allowed
- S = solids (vs. liquids, which show different markings)
- 23 = year of manufacture
- CN = country of origin (China)
- XYZ = testing facility code
Packing groups determine packaging strength
Your dangerous goods will fall under:
- Packing Group I— great danger
- Packing Group II — medium danger
- Packing Group III— low danger
Typically, higher hazard levels require stronger, more expensive packaging.
Common types of UN packaging available in China
Chinese suppliers and DG warehouses typically offer:
- UN-certified 4G fiberboard boxes
- UN plastic or steel drums
- UN jerricans (1H1, 1H2)
- UN IBCs (31HA1, 31HG1)
- UN packaging for lithium batteries (fiberboard with foam inserts)
- UN pails for paints, adhesives, and coatings
How to verify UN certification
Before shipping, always confirm:
- The UN code matches your product’s packing group
- The manufacturing year is still valid
- Follow closure instructions exactly
- Do not exceed weight limits
- The packaging material is compatible with your product
Need help selecting the correct UN-certified packaging? ASLG provides on-site checks, repacking, and full DG compliance support.
Different packaging requirements by DG category
Based on ASLG’s experience handling thousands of DG shipments from China, here are the most common packaging requirements you should be aware of.
Class 3 – Flammable liquids
Examples include: solvents, alcohols, adhesives, inks, and perfumes.
Key packaging considerations:
- Use leakproof inner containers
- Add sufficient absorbent materials inside each box
- Apply UN 4G fiberboard boxes for most consumer liquid products
- For excepted quantities → apply the excepted quantities label (Class 3)
- For limited quantities → follow LQ packaging rules
For example: cleaning agents, acids, alkalis, battery electrolyte solutions.
Packaging must emphasize chemical compatibility:
- Inner bottles must resist chemical reaction or degradation
- Liquids require extra absorbent material
- Metal containers are often unsuitable or prohibited
- Drums may require special lining or coating
Examples: hydrogen peroxide, bleaching powders.
Essential packaging requirements:
- Strong, airtight closures
- Protection from heat sources
- Separation from combustible materials
- Certified drums or pails for liquids
- Sealing standards must match the UN test report exactly.
Lithium battery packaging follows its own strict rules:
- Use UN-certified fiberboard packaging
- Add short-circuit protection (foam, trays, or inner sleeves)
- Secure cells so they cannot shift during transport
- Follow air-transport SOC (state of charge) limits
From ASLG’s experience, poor internal cushioning and loose cells remain the top reasons for battery rejection at origin airports in China.
How to know if your packaging is compliant (practical checklist)
Before sending your dangerous goods to the airport or port, use this quick compliance checklist:
- Do you have the correct UN-certified packaging for your packing group?
- Did you follow the closure instructions exactly as stated in the test report?
- Are the inner containers chemically compatible with your product?
- Did you add absorbent material (for liquid shipments)?
- Is there zero movement inside the box after sealing?
- Are the hazard labels the correct size (typically 100 mm) and correctly placed?
- Did you remove all old or conflicting labels?
- Is the UN number clearly visible on the box or drum?
- For lithium batteries: Is the packaging UN-certified and properly tested?
- For LQ shipments: Is the Limited Quantity label applied?
- For EQ shipments: Is the triple-layer packaging correct?
- Is the packaging clean, dry, and undamaged?
If you cannot confidently answer YES to every item, your shipment may fail DG acceptance, and repacking is usually necessary.
Limited quantity vs. excepted quantity packaging
Many shippers hear these terms but misunderstand the difference. The two are not interchangeable.
1. Limited Quantity Packaging (LQ)
Use LQ when:
- Each inner packaging stays within the LQ limit for its UN number
- The total gross weight per box is within the allowed maximum
Labeling requirements:
- Black-and-white LQ diamond label
- UN number not required inside the diamond
Benefits:
- Lower DG surcharges
- Simplified documentation
- Often accepted by express couriers
LQ packaging must still be strong and durable, but UN-certified packaging is usually not required.
2. Excepted Quantity Packaging (EQ)
EQ applies to very small quantities (usually in milliliters).
Requirements:
- Triple-layer packaging (inner + intermediate + outer)
- Correct the expected quantities label for Class 3 or the applicable hazard class
- Compliance with strict maximum net quantity limits
Benefits:
- Very low DG cost
- Often exempt from the DG declaration
- Ideal for cosmetic samples, laboratory materials, R&D shipments, and small consumer bottles
However, EQ packaging must pass specific drop-test standards, and many Chinese suppliers fail to prepare it correctly without clear guidance.
How ASLG helps you ship dangerous goods safely
We understand that packaging is the part of DG shipping that most shippers struggle with, especially when buying from different factories across China.
Our DG team assists you by:
- Inspecting packaging directly at the factory or warehouse
- Selecting the correct UN-certified packaging for your cargo
- Providing professional repacking services for all DG classes
- Applying accurate DG labels and markings per airline and IMO rules
- Guiding DG documentation such as MSDS, UN38.3, test reports, and more
- Managing door-to-port or door-to-door DG transportation
- Coordinating DG acceptance with airlines and shipping lines to prevent rejection
