Marking and Labels on Containers for Dangerous Goods
Introduction to Marking and Labeling of Dangerous Goods
Marking and labeling of containers for dangerous goods represents a fundamental pillar of chemical and logistics safety. In global transport, storage and handling of chemicals, gases, explosives and other hazardous materials, proper marking is essential for protecting human health, property and the environment. This system is not random — it is based on detailed international regulations (ADR, IMDG, GHS, CLP) and technical standards.
Purpose of marking and labeling:
- Immediately and clearly inform about the nature of the container’s contents, its risks and handling requirements.
- Ensure protection of workers, emergency services and the general public in case of an extraordinary event.
- Ensure compliance with legal regulations (e.g. ADR, RID, IMDG, CLP), whose non-compliance can have serious legal and financial consequences.
What is marking used for in practice?
- Hazard identification: Quick recognition of whether the container contents are flammable, toxic, corrosive, explosive or otherwise hazardous.
- Safe handling: Provides instructions and warnings for proper handling, storage and transport.
- Crisis management: Enables rapid and effective response by firefighters, rescue workers and environmental agencies in case of leakage, fire or accident.
- Error prevention: Minimizes the risk of substance confusion, cross-contamination or inappropriate storage.
Legal Framework and Basic Standards
International and European Regulations
| Abbreviation | Name | Scope of Application |
|---|---|---|
| GHS | Globally Harmonized System of Classification and Labeling of Chemical Substances (UN) | Basic framework for classification and marking of substances and mixtures |
| CLP | Regulation (EC) No. 1272/2008 (Classification, Labelling and Packaging) | European Union, implementation of GHS into EU law |
| ADR | European Agreement concerning the International Carriage of Dangerous Goods by Road | Road transport in Europe and adjacent countries |
| RID | Regulations concerning the International Carriage of Dangerous Goods by Rail | Rail transport |
| IMDG Code | International Maritime Dangerous Goods Code | Maritime transport |
| IATA DGR | International Air Transport Association Dangerous Goods Regulations | Air transport |
Each legal standard determines detailed requirements for:
- Classification of hazardous substances and mixtures (classes, UN numbers, official names, packing groups)
- Method of marking and labeling, dimensions and placement of marks
- Obligations of transport participants, training, documentation
Classification of Dangerous Goods — 9 Classes
All hazardous substances fall into one of the following classes (according to the UN “Orange Book”):
| Class | Name | Examples | Key Risk |
|---|---|---|---|
| 1 | Explosives | Explosives, pyrotechnics | Explosion, detonation |
| 2 | Gases | Propane, acetylene, oxygen | Flammability, toxicity |
| 3 | Flammable Liquids | Gasoline, ethanol, paints | Combustion, vapors |
| 4 | Flammable Solids | Sulfur, phosphorus | Self-ignition |
| 5 | Oxidizing Substances | Ammonium nitrate | Oxidation, reaction |
| 6 | Toxic/Infectious Substances | Cyanides, pesticides | Poisoning, infection |
| 7 | Radioactive Materials | Isotopes, uranium | Radiation |
| 8 | Corrosives | Sulfuric acid | Corrosion, erosion |
| 9 | Miscellaneous Hazardous Substances | Lithium batteries, asbestos | Various risks |
Each class has assigned specific labels, placards and requirements for packaging or handling.
Key Elements of Marking and Labeling
UN Number
- Four-digit code (e.g. UN 1203 for gasoline)
- Mandatory on packaging, container and in transport documentation
- Enables precise identification of the substance in the international database

Official Shipping Name (PSN — Proper Shipping Name)
- Standardized name of the substance according to UN Model Regulations
- Must be identical on all documents and markings
Packing Group (PG)
- Determines the degree of hazard:
- I – high risk
- II – medium risk
- III – lower risk
- Marking directly on the packaging: e.g. “UN 4G/Y30/S/22/D/BAM1234”
Pictograms and Safety Labels
- Diamond labels (100×100 mm) on individual items
- Placards (250×250 mm) on outer walls of containers
- Orange tables (400×300 mm) with UN number and hazard code on vehicles and containers
| Symbol | Meaning | Class |
|---|---|---|
| Explosives | 1 | |
| Gases | 2 | |
| Flammable Liquids | 3 | |
| Corrosives | 8 | |
| … | … | … |
Labels must be durable, clearly visible and must not be covered by other objects or soiled.
Difference Between Marking and Labeling
Labeling:
- Placement of standardized labels containing pictograms, signal words, H- and P-statements
- Used mainly on consumer and work packaging according to GHS/CLP
Marking:
- Broader concept: includes labels and other mandatory information (UN number, safety marks — placards, official name, handling instructions)
- Mandatory on transport containers, tanks, vehicles
Structure of Label According to GHS/CLP
Each label must contain these elements:
- Product name / identifiers
- Hazard pictograms (see above)
- Signal word (“Danger” / “Warning”)
- Standard H-statements (for example: H225 – Highly flammable liquid and vapors)
- P-statements (recommendations for safe handling, e.g. P210 – Keep away from heat)
- Supplier identification (name, address, phone)
- UN number and official shipping name (on transport packaging)
Table of Examples:
| Label Element | Description | Example |
|---|---|---|
| Product Name | Chemical substance / mixture | Acetone |
| Pictogram | Flammability symbol | |
| Signal Word | DANGER | DANGER |
| H-statement | Nature of Hazard | H225: Highly flammable liquid and vapors |
| P-statement | Prevention | P210: Keep away from heat and open flame |
| Supplier | Identification | ChemCo Ltd., Prague, tel. 123 456 789 |
Types of Containers and Marking Requirements
ISO Containers
- Most commonly 20′ and 40′ feet (ISO 668)
- Must have fixed safety marks on both longer and shorter sides (min. 250×250 mm)
- Orange tables with UN number (400×300 mm) on front and rear of vehicle transporting the container
Tank Containers
- Additionally marked with tank code, maximum operating pressure and volume information
- Special marking for pressurized gases, explosives, radioactive materials
Smaller Packages Inside Container
- Each individual package must be labeled according to GHS/CLP and UN number
Specifics of ADR Marking
ADR — European Agreement on Road Transport
- Marking of containers and vehicles is strictly standardized
- Mandatory elements (summary):
| Element | Size | Location | Specifics |
|---|---|---|---|
| Orange Table | 400×300 mm | Front and rear of vehicle | Reflective, fire resistance min. 15 min |
| Safety Placards | 250×250 mm | Both sides and both ends of container | Corresponding hazard inside |
| Identification Numbers | 100 mm | On orange table | Upper part — hazard code, lower — UN number |
- Exceptions: Some substances have different or supplementary marking (e.g. Class 7 — radioactive materials)
Practical Examples of Container Marking
Example 1: Transport of Gasoline (UN 1203, Class 3, PG II)
| Element | Location | Text/Symbol |
|---|---|---|
| Orange Table | Front and rear of vehicle | 33 / 1203 (33 = highly flammable liquid, 1203 = gasoline) |
| Safety Placard | Both side walls and both ends of container | Flame symbol, Class 3 |
| Label on Package | Each canister inside | GHS02, H225, P210, supplier identification |
Example 2: Transport of Sulfuric Acid (UN 1830, Class 8, PG II)
| Element | Location | Text/Symbol |
|---|---|---|
| Orange Table | Front and rear of vehicle | 80 / 1830 |
| Safety Placard | Both side walls and both ends of container | Corrosive symbol, Class 8 |
| Label on Package | Each drum inside | GHS05, H314, P280, supplier identification |
Correct Application of Marking — Common Errors and Consequences
- Errors in UN number or PSN: Can lead to substance confusion, inappropriate response in case of accident and legal penalties
- Damaged or illegible labels: Inspection authorities may detain the shipment, impose a fine or stop operations
- Missing signal word or pictogram: Occupational safety hazard, risk of injury
- Incorrect label placement: Non-compliance with regulations, fine, possible deterioration of crisis response
Digitalization and Modern Trends
Electronic Safety Data Sheets and QR Codes
- Modern labels contain QR or barcode that allows immediate access to current Safety Data Sheet (SDS)
- Digitalization enables efficient chemical management, employee training, error minimization
Centralized Databases
- SDS management in company databases, automatic updates and compliance monitoring with regulations
Online Training and E-learning
- Mandatory ADR training, GHS/CLP for all employees handling hazardous substances
Ensuring Safety During Transport and Storage
| Area | Obligations and Recommendations |
|---|---|
| Training | Mandatory for drivers (ADR), handlers, warehouse workers |
| Documentation | ADR transport document, written instructions for accidents, safety data sheets |
| Cargo Securing | Physical security against shifting, leakage or damage |
| Inspections | Regular inspections of marking, label and document updates |
| Crisis Plan | Internal procedures for leakage, fire, accident — all employees must be informed |
Frequently Asked Questions (FAQ)
How often do labels need to be checked and possibly renewed?
- At minimum before each transport, with each package handling and whenever the label is damaged.
- If the substance composition changes or regulations are updated, the label must be updated immediately.
Who is responsible for correct container marking?
- Both the shipper (manufacturer, distributor) and the carrier. Each link in the logistics chain has clearly defined obligations.
What are the penalties for violating regulations?
- Fines up to millions of CZK, suspension of operations, criminal liability in case of injury to health or environment.
Related Terms
- Safety Data Sheet (SDS/MSDS): Detailed document on chemical substance, risks, first aid, fire measures, waste disposal
- Hazardous Waste: Waste with properties of hazardous substance, requires special marking and disposal
- Hazard Class: Classification according to main risk (see above)
- UN Number: International identifier of hazardous substance
Other container news...
Shipping Containers Barcelona Spain
Shipping containers are the backbone of modern global trade, and the Port of Barcelona is one of the most important nodes in this network. Understanding how containers work, what their standards are and how cargo is handled in the Port of Barcelona is essential for anyone involved in international commercial transport. The Port of Barcelona continues to invest in digitalisation, automation and environmental sustainability to maintain its position as one of the most important ports in Europe and the world.
Spare Parts for Shipping Containers Spain
Spare parts for shipping containers are an essential part of the global maritime logistics system. Without them, the thousands of containers that travel the world’s oceans and roads every day would not be able to be maintained in working order. Whether you’re looking for a replacement door handle, a new lock, a gasket or a complete floor, this guide will provide you with all the information you need to find the right parts, install them and maintain them — with a special focus on availability and suppliers in Spain and surrounding countries.
Container Units 20′ – 6m (Construction Unit)
20′ (6 meter) construction cells are one of the most important elements of modern construction and temporary project solutions. These mobile units, created from the conversion of shipping containers, have become an indispensable tool for builders, designers and construction managers around the world.
Demurrage: Port Storage Fees
Demurrage is a time-based fee charged when loaded shipping containers remain in a port or terminal longer than the allotted free time. The term comes from the French word demeurer, meaning “to remain or linger”, and originally arose in the context of ship chartering in the maritime trade. In modern container shipping, demurrage serves as a financial penalty and incentive mechanism to ensure the efficient movement of containers through ports and prevent their indefinite storage at terminals.