What substances are classified as IMDG Class 8 corrosives?

Class 8 covers substances that cause full-thickness destruction of intact skin tissue within an observation period of up to 14 days starting after an exposure time of up to 4 hours. This includes: acids (sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid), alkalis/bases (sodium hydroxide/caustic soda, potassium hydroxide, sodium carbonate, ammonia solution), and other corrosive liquids and solids such as battery acid/electrolyte, cleaning chemicals, descaling agents, and certain metal treatment solutions. Class 8 also covers substances that corrode steel or aluminum at a rate exceeding 6.25 mm per year.

What packaging is required for Class 8 corrosives from China?

Class 8 requires UN-certified packaging made of corrosion-resistant materials compatible with the specific acid or alkali. Glass carboys in protective outer packaging are common for small volumes. UN-approved plastic jerricans (1H1) are used for volumes up to 60L. Steel drums with internal corrosion-resistant linings are used for strong acids (sulfuric, hydrochloric) up to 220L. IBCs (Intermediate Bulk Containers) and ISO tank containers serve bulk shipments. PG I (most corrosive — full skin destruction within 3 minutes) requires the most robust packaging. All packages must display upward orientation arrows (ISO 780) because corrosives must be transported upright to prevent cap/closure contact.

Do all carriers accept Class 8 corrosive shipments from China?

Class 8 has the widest carrier acceptance of all DG classes after Class 3. Nearly all major carriers — MSK, HPL, MSC, COSCO, HMM, OOCL, EMC, YML, and CMA CGM — accept Class 8 for sea freight, including PG I on most routes. This is because Class 8 substances do not present fire or explosion risks, and the primary hazard (corrosion) is contained by proper packaging. Air freight has quantity limits: PG I is generally prohibited on passenger aircraft; PG II limited to 1L per inner packaging on passenger aircraft, 30L on cargo-only; PG III 5L passenger, 60L cargo-only.

Can you ship mixed acids or mixed corrosives from China?

Yes, but classification requires careful analysis. Mixed acids (e.g., nitrating acid — a mixture of nitric acid and sulfuric acid, UN1796) and other corrosive mixtures (UN1760 — corrosive liquid N.O.S.) are common. The mixture's UN number depends on the dominant hazard and specific composition. Key considerations: the MSDS must specify the exact composition percentages, the mixture must be tested for skin corrosion to determine the correct packing group, and mixing must be done by the manufacturer under controlled conditions — never mix acids at the port or in transit. Some mixtures (e.g., nitric acid + organic compounds) can be both corrosive (Class 8) and oxidizing (Class 5.1), requiring dual classification.

Class 8 Corrosives Freight from China | DG Export Shipping

All DG Classes

IMDG Class 8 covers substances that cause severe damage to living tissue, other materials, or the means of transport through chemical reaction. This includes both acids and alkalis (bases). Class 8 is the second most commonly shipped DG class from China after Class 3, reflecting the country's dominant position in global chemical manufacturing. China produces over 30% of the world's sulfuric acid, 20% of sodium hydroxide, and is the largest exporter of phosphoric acid and many industrial cleaning chemicals.

Class 8 Packing Groups

Packing Group I: Causes full-thickness skin destruction within 3 minutes of exposure (observation period up to 60 minutes). Examples: sulfuric acid >51%, hydrofluoric acid >60%, nitric acid >70%. Most restricted packaging requirements.
Packing Group II: Causes full-thickness skin destruction within 3-60 minutes of exposure (observation period up to 14 days). Examples: hydrochloric acid (muriatic acid), phosphoric acid, sodium hydroxide solutions >40%, battery acid (sulfuric acid 30-51%). Most common PG for industrial corrosives.
Packing Group III: Causes full-thickness skin destruction within 4-14 days of exposure, or corrodes steel/aluminum at >6.25 mm/year at 55°C. Examples: dilute acetic acid (>10%), sodium hypochlorite solution (household bleach), certain cleaning products.

Product Examples by UN Number

Acids

Sulfuric acid (UN1830): The single highest-volume DG product from China. Over 90 million tons produced annually. Ships in ISO tank containers (T11), IBCs, or drums. PG II for concentrations up to 51%; above 51% is PG I. Used in fertilizer production, metal processing, and chemical synthesis.
Hydrochloric acid (UN1789): Muriatic acid. Major by-product of China's chlor-alkali industry. PG II or III depending on concentration. Ships in plastic drums or rubber-lined steel.
Nitric acid (UN2031): Strong acid and oxidizer. PG I (>70%) or PG II (≤70%). Red fuming nitric acid has separate provisions. Used in fertilizer and explosives manufacturing.
Phosphoric acid (UN1805): Food-grade and industrial-grade. China is the world's top exporter. PG III. Ships in IBCs and ISO tanks. Key ingredient in fertilizers and food/drink additives.
Hydrofluoric acid (UN1790): Extremely hazardous — penetrates skin and attacks bone. PG I (>60%) or PG II (≤60%). Ships in polyethylene containers only (dissolves glass). Limited carrier acceptance.
Formic acid (UN1779): Leather tanning, textile processing. PG II. Ships in plastic drums or stainless steel.
Acetic acid, glacial (UN2789): Concentrated acetic acid. PG II. Flammable above 39°C — also has Class 3 characteristics at certain concentrations. Ships in aluminum or stainless steel containers (corrodes carbon steel).

Alkalis (Bases)

Sodium hydroxide / Caustic soda (UN1823/UN1824): Solid (UN1823, PG II) or solution (UN1824, PG II or III). China is the world's largest producer via chlor-alkali process. Ships in 25kg bags (solid flakes/pearls), drums, or ISO tanks (solution). Major export for soap, paper, and textile industries.
Potassium hydroxide / Caustic potash (UN1813/UN1814): Similar to caustic soda. PG II for solid, PG II/III for solution. Liquid soap, biodiesel catalyst.
Sodium carbonate / Soda ash (not always DG): Only classified as Class 8 if in concentrated solution form. Dry soda ash is generally non-DG.

Other Corrosives

Battery acid / electrolyte (UN2796): Sulfuric acid solution typically 30-38% concentration. PG II. Ships in dedicated acid-resistant packaging. Lead-acid batteries containing electrolyte may also fall under Class 8.
Sodium hypochlorite solution (UN1791): Bleach, pool chlorine liquid. PG II (>5% available chlorine) or PG III (≤5%). Ships in plastic drums or IBCs. Must be segregated from acids (releases toxic chlorine gas).
Cleaning chemicals / Descaling agents (UN1760/UN3264/UN3265): Many industrial and household cleaning products are Class 8 due to acid or alkali content. UN1760 is the catch-all "corrosive liquid N.O.S." classification.
Ferric chloride / ferrous chloride solution (UN2582/UN1760): Water treatment and electronics etching. PG III. Ships in plastic drums.

Packaging Requirements

Material compatibility is paramount: The container material must resist the specific corrosive for the entire duration of transport. Sulfuric acid corrodes carbon steel; hydrofluoric acid dissolves glass; nitric acid attacks most plastics. Always verify container material from the MSDS compatibility table.
UN-certified containers: Drums (1A1 steel, 1H1 plastic), jerricans (3H1 plastic), IBCs (31HA1 composite), ISO tanks. All must display UN specification markings with the test pressure and approved packing group.
Orientation arrows (ISO 780): Mandatory on all liquid corrosive packages. Packages must be loaded, stowed, and transported upright. Closures must not be in contact with the liquid during transport.
Vented caps for some acids: Nitric acid and hydrogen peroxide-containing products may require vented closures to allow gas release without leakage. Check MSDS for venting requirements.
Secondary containment: For PG I liquids on-deck stowage, drip trays or bunding in the container to contain any leakage is recommended.
Segregation: Class 8 must be segregated from Class 5.1 (oxidizers), Class 6.1 (toxic when both liquid), and foodstuffs. Acids and alkalis should ideally be segregated from each other (separate containers).

Carrier Acceptance Table

Carrier	PG I	PG II	PG III	Air Freight
MSK	Accepted	Accepted	Accepted	PG II/III limited
HPL	Accepted	Accepted	Accepted	PG II/III limited
MSC	Accepted	Accepted	Accepted	PG II/III limited
COSCO	Accepted	Accepted	Accepted	PG III only
HMM	Accepted (case-by-case)	Accepted	Accepted	Not offered
OOCL	Accepted	Accepted	Accepted	PG III limited
EMC	Accepted	Accepted	Accepted	Not offered
YML	Accepted (case-by-case)	Accepted	Accepted	Not offered
CMA CGM	Accepted	Accepted	Accepted	PG II/III limited

Class 8 has the most carrier-friendly acceptance profile of any DG class. Near-universal acceptance for sea freight across all three packing groups. Air freight accepts PG II and PG III on cargo aircraft with quantity limits.

Port Comparison for Class 8 Exports

Qingdao Port: The recommended port for most Class 8 exports. Qingdao's DG terminal has acid-resistant flooring in designated areas, dedicated spill containment systems, and trained DG stevedores for acid/alkali handling. The port handles high volumes of Shandong's chemical manufacturing output (caustic soda, soda ash, sulfuric acid). Strongest sailing frequency to Asia, South America, Middle East, and Africa.

Shanghai Port: Best for European and North American destinations with the widest carrier selection. Higher throughput means longer DG filing queues but also the most frequent sailings. Preferred for ISO tank shipments to Europe.

Tianjin Port: Important for northern China's chlor-alkali industry exports. Strong carrier connections to Russia and Central Asia. Dedicated chemical terminal at Tianjin Nangang.

Documentation Checklist

MSDS — must state pH, concentration, material compatibility, and skin corrosion test data
DG Packaging Certificate (危包证) — with corrosion-resistance notation
Maritime DG Declaration
Port Filing Approval
Container material compatibility certificate (recommended for PG I)
ISO tank certificate (for bulk acid/alkali shipments in tanks)
Commercial Invoice, Packing List, B/L with DG endorsement
Carrier DG Booking Confirmation

Frequently Asked Questions

Can I ship sulfuric acid and sodium hydroxide in the same container?

No. Acids and alkalis must never be shipped in the same container. If a leak were to occur, the acid-alkali reaction would generate intense heat, release hazardous fumes, and could rupture the packaging of both substances. The IMDG Code requires at minimum "separated from" stowage (different containers, or separated by at least 3 meters in the same hold). We always ship acids and alkalis in separate containers, on separate bills of lading, to eliminate any risk of mixing.

Why are orientation arrows mandatory for Class 8 liquids?

Orientation arrows are critical because corrosives must be transported with closures upward. If a corrosive liquid container is stored on its side, the closure (cap, bung, valve) is in constant contact with the corrosive substance, significantly increasing the risk of closure degradation and leakage. Additionally, many closures are designed with pressure relief that functions correctly only in the upright position. Transporting corrosives in any orientation other than upright is a violation of IMDG Code 5.2.1.7 and can result in container rejection at the port.

Can I ship household cleaning products from China without DG classification?

Not always. Many household cleaning products contain corrosive ingredients (bleach, drain cleaner, toilet bowl cleaner, oven cleaner) that meet Class 8 criteria. Sodium hypochlorite (bleach) above 5% available chlorine is Class 8 UN1791 PG II. Drain cleaners containing sodium hydroxide above 5% may be Class 8 UN1824. The key is the MSDS: if the product is labeled as corrosive (skin corrosion pictogram) or has pH below 2 or above 11.5, it likely requires Class 8 classification. Small consumer-packaged products (<1L) may qualify for Limited Quantity (LQ) provisions with reduced requirements.

Can Class 8 corrosive solids ship from China? What are examples?

Yes. Class 8 includes corrosive solids as well as liquids. Common examples: sodium hydroxide solid/flakes/pearls (UN1823), potassium hydroxide solid (UN1813), chromic acid solid (UN1463), and certain metal cleaning compounds. Solid corrosives have slightly simpler packaging requirements than liquids — no orientation arrows are required, but they still need UN-certified packaging rated for the packing group, moisture-barrier packaging (many solid alkalis are hygroscopic and absorb moisture from air), and the same hazard labeling. Dust from corrosive solids can be as hazardous as liquid splashes.

Class 8 — Corrosive Substances: Freight from China