IMDG Class 3 is the most commonly shipped dangerous goods class globally, covering all liquids with a flash point of 60°C or below. From industrial solvents and paints to consumer products like perfumes and nail polish, Class 3 shipments dominate DG export volumes from China. The class is divided into three packing groups based on flash point and boiling point, with each PG dictating packaging standards, stowage requirements, and mode-of-transport options.
Class 3 Packing Groups
The packing group (PG) system is critical for Class 3 because it determines packaging performance requirements and whether air freight is even an option:
- Packing Group I (PG I): Flash point below -18°C and initial boiling point ≤35°C. The most dangerous category. Examples: diethyl ether (UN1155), carbon disulfide (UN1131). Very limited carrier acceptance; almost exclusively ships by sea.
- Packing Group II (PG II): Flash point below 23°C. The most common PG for industrial solvents and chemicals. Examples: acetone (UN1090), ethanol (UN1170), methanol (UN1230), toluene (UN1294). Accepted by most carriers for sea freight; limited quantities on cargo aircraft.
- Packing Group III (PG III): Flash point 23°C to 60°C. The least restrictive PG. Examples: diesel fuel (UN1202), certain paints (UN1263 PG III), some printing inks. Broadest carrier acceptance; more air freight options.
Product Examples by UN Number
Common Class 3 products exported from China:
- UN1090 — Acetone: Solvent for paints, adhesives, and cleaning. High-volume export from China's chemical industry.
- UN1170 — Ethanol (Ethyl Alcohol): Industrial alcohol, hand sanitizer base, beverage alcohol. China is a major ethanol exporter.
- UN1203 — Gasoline: Motor fuel. Ships in drums or ISO tanks. Special regulations apply for bulk shipments.
- UN1219 — Isopropanol (Isopropyl Alcohol): Electronics cleaning, pharmaceutical solvent. High-purity grades for semiconductor manufacturing.
- UN1263 — Paint / Paint-Related Materials: The single most common Class 3 UN number from China. Covers paints, varnishes, enamels, lacquers, and thinners. Packing group varies by flash point.
- UN1866 — Resin Solution: Epoxy, polyurethane, and alkyd resin solutions for coatings and adhesives.
- UN1993 — Flammable Liquid N.O.S.: Catch-all for mixtures not specifically listed. Requires precise chemical description on the MSDS and DG declaration.
- UN1133 — Adhesives: Industrial adhesives containing flammable solvents. Common in footwear, furniture, and packaging industries.
- UN1210 — Printing Ink: Solvent-based and UV-curable inks. High-volume export from China's printing industry supply chain.
- UN1266 — Perfumery Products: Fragrances, essential oils, cosmetic bases with flammable solvents.
Packaging Requirements
Class 3 flammable liquids require UN-certified packaging appropriate to the packing group. The packaging must prevent leakage, withstand internal pressure from vapor buildup, and protect against external impact:
- UN-approved jerricans (1H1/3H1): Plastic jerricans rated for the appropriate PG. Most common for volumes up to 25L.
- UN-approved steel drums (1A1/1A2): For larger volumes (up to 220L). Required for PG I liquids and preferred by many carriers.
- IBCs (Intermediate Bulk Containers): For 1,000L+ volumes. Must be UN-rated (31HA1/31A). Only permitted for PG II and PG III.
- ISO tank containers (T11/T14): For bulk shipments of 20,000L+. Requires specialized DG tank operators and port handling.
- Inner + outer combination packaging: Glass or plastic inner containers (max 5L for PG II, max 60L for PG III) packed with absorbent material in UN-certified fiberboard outer boxes.
All packaging must display the Class 3 flammable liquid hazard label (red background with flame symbol) and the correct UN number. For PG I and PG II, the flash point must be noted.
Carrier Acceptance for Class 3
| Carrier | PG I | PG II | PG III | Air Freight |
|---|---|---|---|---|
| MSK | Accepted (restricted) | Accepted | Accepted | PG II/III only (CAO) |
| HPL | Case-by-case | Accepted | Accepted | PG II/III limited |
| MSC | Accepted | Accepted | Accepted | PG II/III limited |
| COSCO | Case-by-case | Accepted | Accepted | PG III only |
| HMM | Not accepted | Accepted | Accepted | Not offered |
| OOCL | Case-by-case | Accepted | Accepted | PG III limited |
| EMC | Not accepted | Accepted | Accepted | Not offered |
| YML | Case-by-case | Accepted | Accepted | Not offered |
| CMA CGM | Case-by-case | Accepted | Accepted | PG II/III limited |
PG I is the most restricted packing group. Always confirm carrier PG I acceptance on your specific route before booking. Air freight acceptance is for cargo-only aircraft (CAO) only; passenger aircraft restrictions are tighter.
Port Comparison for Class 3 Exports
Qingdao Port: Best for PG II and PG III liquids. Dedicated DG liquid handling areas with spill containment. Strongest sailing frequency to South America, Africa, and Middle East. Recommended for high-volume Class 3 exports.
Shanghai Port: Widest carrier choice for European and North American destinations. Better air freight connectivity for time-sensitive PG III shipments via Pudong airport. Higher DG filing volumes can mean longer processing times.
Tianjin Port: Serves northern China chemical manufacturing clusters (Hebei, Liaoning). Particularly strong for ISO tank shipments to Russia and Central Asia.
Documentation Checklist for Class 3
- MSDS (Material Safety Data Sheet) — GHS-compliant, must state flash point
- DG Packaging Certificate (危包证) — UN performance-tested for correct PG
- Maritime DG Declaration — filed with MSA, must cite flash point
- Port Filing Approval
- Commercial Invoice (with "DG Class 3, UN[number]" notation)
- Packing List (itemize each package type and UN spec marking)
- Bill of Lading with DG endorsement
- Carrier DG Booking Confirmation
- Flash Point Test Report (recommended for PG I and PG II)
Frequently Asked Questions
What is the difference between Class 3 flammable liquids and combustible liquids?
Under the IMDG Code, the term "combustible liquid" is not a separate class. All liquids with flash point ≤60°C are Class 3. Liquids with flash points above 60°C but below 93°C may be regulated as "elevated temperature liquids" under Class 9 (UN3257) if transported at or above their flash point, but are not Class 3. This is a common point of confusion — always check the MSDS for the correct classification.
Can I ship paint by sea from China without a DG certificate?
Only if the paint's flash point is above 60°C (non-Class 3) and it contains no other hazardous components. Most industrial and decorative paints have flash points below 60°C due to solvent content and are firmly Class 3 UN1263. Water-based paints with very low solvent content may fall below the DG threshold, but the MSDS must confirm this. We always recommend obtaining a formal classification from the manufacturer before deciding to ship as non-DG — misdeclaration can result in container rejection, fines, and port blacklisting.
Can essential oils and perfumes ship as Class 3 from China?
Yes. Perfumes and essential oils containing flammable solvents (typically ethanol) are Class 3 UN1266. The packing group depends on ethanol concentration and flash point. Many perfumes fall under PG II or PG III. Consumer-packaged perfumes in small bottles may qualify for Limited Quantity (LQ) provisions, which reduce some packaging and labeling requirements. However, bulk perfume shipments (drums or IBCs) must follow full Class 3 regulations.
What happens if my Class 3 cargo leaks during transit?
A Class 3 leak at sea is a serious incident. The vessel will declare an emergency, the leaking container may be isolated or jettisoned, and the shipper bears full liability for cleanup costs, vessel delay charges, and potential environmental penalties — costs that can exceed USD 1 million. This is why proper UN packaging, professional container stuffing with secondary containment, and DG-experienced loading supervision are not optional. Our DG team includes on-site container stuffing supervision for all Class 3 shipments.