Dangerous Goods Class 3: Flammable Liquids

Dangerous Goods Class 3 refers to flammable liquids under international dangerous goods transport classification. Alcohols, solvents, paints, adhesives, inks, perfumes, fuels, cleaning agents and similar products may fall under Class 3 depending on their composition and flash point.

Whether a product is Class 3 cannot be decided from the commercial product name alone. Forwarders should check the SDS, flash point, boiling point or initial boiling point, UN number, proper shipping name, packing group and transport-mode-specific requirements before arranging booking, storage or cargo delivery.

Class 3 cargo appears frequently in international logistics. Because it may involve leakage, vapor generation, ignition risk, storage restrictions and carrier acceptance issues, early document checking is essential.

Overview

Class 3 covers flammable liquids that may ignite under certain conditions. The practical risk is not limited to the liquid itself. Vapor, leakage, damaged containers, heat, static electricity, poor ventilation and contact with ignition sources may create serious safety problems.

In sea transport, Class 3 cargo is checked under the IMDG Code. In air transport, it is checked under the IATA Dangerous Goods Regulations and airline acceptance rules. Warehouses, CFS operators, trucking companies and domestic delivery providers may also apply their own acceptance conditions.

For Japan-bound cargo, forwarders should also consider whether domestic storage or handling may require confirmation under Japanese fire safety or warehouse rules. Transport classification and domestic storage classification should not be treated as exactly the same question.

Main Items to Check

For Class 3 cargo, the SDS transport section should be checked first. The following items are especially important:

• UN number
• Proper shipping name
• Whether the cargo is classified as Class 3
• Packing group
• Flash point
• Boiling point or initial boiling point
• Subsidiary risk, if any
• Marine pollutant status, where applicable
• Whether Limited Quantity or Excepted Quantity provisions may apply
• Differences between sea transport, air transport and domestic handling

If any of these points are unclear, the shipper or manufacturer should be asked to confirm the classification before the cargo is accepted.

Relationship with Packing Group

For flammable liquids, the packing group is used to indicate the degree of danger. In Class 3, the initial boiling point and closed-cup flash point are important factors in determining whether the cargo falls under Packing Group I, II or III.

Packing Group	General Risk Level	Typical Class 3 Check Point
I	High danger	Initial boiling point of 35°C or below
II	Medium danger	Initial boiling point above 35°C and flash point below 23°C
III	Lower danger	Initial boiling point above 35°C and flash point of 23°C to 60°C

In practice, the forwarder should check whether the packing group shown in the SDS matches the dangerous goods declaration, labels, packaging, booking information and carrier requirements.

The packing group should not be guessed from the product name. It should be confirmed from SDS, manufacturer information or applicable dangerous goods classification data.

Practical Handling Flow

When handling Class 3 cargo, dangerous goods information should be confirmed at an early stage. If booking or delivery is arranged before the classification is confirmed, the cargo may be refused by the shipping line, airline, CFS or warehouse.

1. Obtain the SDS and check the transport section.
2. Confirm the UN number, proper shipping name, class and packing group.
3. Check whether a dangerous goods declaration is required.
4. Confirm acceptance with the shipping line, airline, warehouse or CFS.
5. Check approved packaging, labels, marks and packing conditions.
6. Arrange a dangerous goods warehouse or suitable storage area if required.
7. Coordinate receiving date, cut-off date, loading schedule and inspection timing.
8. Pay attention to leakage, ignition, heat exposure and consolidation restrictions.

Main Documents

Class 3 cargo usually requires dangerous goods information in addition to ordinary commercial documents. SDS and the dangerous goods declaration are especially important because they are used by carriers, airlines, warehouses and forwarders to check acceptance.

• SDS, formerly called MSDS
• Dangerous Goods Declaration
• Commercial invoice
• Packing list
• Shipping instruction
• Packaging certificate, test report or manufacturer confirmation, where required
• Container packing certificate or related packing documents, where required

Forwarder Check Points

A forwarder should not treat cargo as ordinary goods merely because the shipper describes it as “paint,” “perfume,” “cleaning agent,” “adhesive” or “alcohol product.” These descriptions often require further checking.

• Is the SDS the latest version?
• Does the SDS transport section show the UN number, Class 3 and packing group?
• Does the dangerous goods declaration match the SDS?
• Does the shipping line or airline accept the relevant UN number?
• Are the conditions different for LCL, FCL and air cargo?
• Is dangerous goods warehouse storage required?
• Could Japanese fire safety or domestic storage rules affect receiving or delivery?
• Are there additional restrictions in the import country?

Sea Transport

For sea transport, Class 3 cargo may affect dangerous goods booking approval, container stuffing, labels, placards, segregation, stowage, CFS receiving and consolidation conditions.

In LCL shipments, the forwarder should confirm whether the cargo can be consolidated with other goods. Even if the cargo is accepted as Class 3, consolidation conditions may differ depending on the UN number, packing group, quantity, packaging, route, shipping line and destination.

Dangerous goods approval and CFS cut-off times may be earlier than ordinary cargo. The classification should therefore be confirmed before cargo delivery to the CFS or CY.

Air Transport

For air transport, Class 3 cargo may be subject to stricter quantity limits, packaging instructions, passenger aircraft restrictions, cargo aircraft only conditions and airline-specific acceptance rules.

Some Class 3 cargo that can be shipped by sea may be restricted or refused by air. Products such as perfumes, alcohol-containing goods, paints, adhesives, solvents, cleaning agents and reagents should be checked before quotation or booking.

If document or packaging defects are found only at the airport or airline warehouse, the cargo may be rejected for loading and the shipment may be delayed.

Storage and Fire Safety Considerations

Class 3 cargo may require special attention during temporary storage. Leakage, vapor generation, heat exposure, poor ventilation and contact with ignition sources can create fire safety risks.

For Japan-bound cargo, storage conditions may also need to be checked separately from transport classification. A cargo classified as Class 3 for transport may require confirmation under Japanese domestic fire safety or warehouse rules before it can be stored or delivered.

Forwarders should check whether a dangerous goods warehouse, temperature control, ventilation, segregation or special receiving procedure is required.

Practical Precautions

• Do not accept damaged containers or leaking cargo.
• Check dangerous goods labels, UN number marks and outer package markings.
• Avoid ignition sources, heat sources, direct sunlight and high-temperature environments.
• Confirm ventilation, temperature control and separated storage where required.
• Do not store Class 3 cargo in inappropriate areas such as corridors, emergency exits or stairways.
• Check for mismatch between the dangerous goods declaration and the actual cargo.
• Check fire safety rules, IMDG Code, air dangerous goods rules and import-country requirements separately.

Common Cargo Examples

Example	Main Use	Practical Check Point
Ethanol	Disinfection, industrial use, raw material	Check concentration, flash point and packing group.
Methanol	Solvent, fuel, raw material	Check toxicity, subsidiary risk and import-country restrictions.
Acetone	Solvent, cleaning agent	Highly volatile; check container condition, ventilation and ignition control.
Paint	Construction or industrial use	Check whether it is water-based or solvent-based and review SDS transport information.
Adhesive	Industrial or consumer use	Check solvent content and whether Limited Quantity provisions may apply.

Common Problems

• The shipper describes the cargo only as paint, perfume, alcohol, cleaning agent or adhesive.
• The SDS is outdated or the transport section is incomplete.
• The flash point is not confirmed.
• The packing group is missing or inconsistent.
• The dangerous goods declaration does not match the SDS.
• The outer package labels or UN number marks are missing.
• Sea transport and air transport conditions are confused.
• The cargo is delivered to a warehouse or CFS before dangerous goods approval is completed.
• Domestic storage or fire safety requirements in Japan are not checked.

These problems may lead to booking delay, cargo receiving refusal, air loading rejection, repacking, relabeling, warehouse transfer, additional costs or liability issues after an incident.

Practical Notes for Shipments to Japan

For Japan-bound Class 3 cargo, origin-side forwarders should confirm dangerous goods information before cargo pickup. Japanese-side parties may ask for SDS, dangerous goods declaration, flash point, packing group, quantity, packaging, labels, warehouse storage conditions and carrier acceptance information.

The issue may arise not only at the time of international transport, but also during CFS receiving, dangerous goods warehouse storage, customs-related checking or domestic delivery in Japan.

For this reason, the forwarder should separate the questions of sea transport acceptance, air transport acceptance, warehouse acceptance, domestic delivery and import-country restrictions.

Key Takeaway

Dangerous Goods Class 3 covers flammable liquids and is one of the most frequently encountered dangerous goods categories in international logistics.

Forwarders should not rely on the product name alone. SDS, UN number, proper shipping name, packing group, flash point, dangerous goods declaration, labels, packaging and transport mode should be checked together.

Early confirmation helps prevent booking delay, warehouse refusal, CFS trouble, air loading rejection, incorrect labelling and unexpected additional costs.