UN Number, Labels, and Panels in ADR Transport
The transport of dangerous goods presents a significant challenge for all components of the supply chain. Safety in these operations is essential, and for information to be universally understood, these goods are marked with what is called the UN Number, a visual marking that acts as a "universal language" allowing transporters, consignors, and emergency services to quickly identify the risks of a substance. In this guide, we want to delve into these key elements, explaining their function and practical application.
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The UN Number: The Unique Substance Identification
The UN Number (or United Nations Number) is a four-digit code assigned to each dangerous substance or article by the UN Committee of Experts. It functions as an international identifier that remains constant, regardless of the country of origin or destination.
What is it for? It allows instant access to the substance's technical data sheet, its properties, risks, and the emergency measures to be followed. It's the first piece of information rescue services look for in case of an incident.
For example, UN 1203 unequivocally identifies petrol, while UN 1005 corresponds to anhydrous ammonia.
Panels and Labels: The Visual Signage of Danger
Signage is a visual communication system prominently displayed on all trailers and tractor units, which alerts to the type of risk posed by the transported goods. It consists of two main elements: the orange panel and the hazard labels.
The Orange Panel: The Vehicle's Identity Card
The orange panel is a fluorescent orange rectangle, visible on the front and rear of the vehicle as well as on the sides of the trailer. It contains two black numbers that provide crucial information about the type of goods being transported:
Hazard Identification Number (Kemler Code):
The upper number (2 or 3 digits) indicates the type of risk:
- 1: Explosive
- 2: Gas
- 3: Flammable Liquid
- 4: Flammable Solid
- 5: Oxidising
- 6: Toxic
- 8: Corrosive
- 9: Miscellaneous Danger
• A doubled digit (e.g., 33) indicates a more intense risk of the primary type.
• An "X" as a prefix (e.g., X338) means the substance reacts dangerously with water.
UN Number: The lower number, which identifies the specific substance.
Reading Example: A 33 / 1203 panel indicates a highly flammable liquid (33) which is petrol (UN 1203).
Hazard Labels: The Risk Pictogram
These labels are the coloured diamonds affixed to packages, containers, and tanks. They have a minimum size of 10x10 cm for packages and 25x25 cm for vehicles (placards). Their design and colour are standardised for each of the 9 ADR classes.
Explosive
Exploding bomb
Gas
Gas cylinder
Flammable Liquid
Flame
Flammable Solid
Flame
Oxidising
Flame over circle
Toxic
Skull and crossbones or biohazard symbol
Radioactive
Radioactive trefoil
Corrosive
Liquids causing corrosion
Miscellaneous Danger
No unique pictogram
Synergy of Elements: Comprehensive Identification
The UN Number, the Kemler Code, and the labels work together to provide a complete "risk map" of the cargo. A transporter can see the panel on the lorry, emergency services can use the UN Number to consult the safety data sheet, and warehouse personnel can identify the package's risk by its label.
Practical Applications and Exemptions
It's crucial to understand that signage varies depending on the quantity transported. For limited quantities (LQ), a simplified diamond symbol is used instead of the class label, which exempts from some vehicle signage requirements.
Frequently Asked Questions
What is the difference between a label and a placard?
Labels are placed on packages and parcels, while larger placards are placed on vehicles and containers.
How do I find the UN Number for my substance?
It can be found in the Safety Data Sheet (SDS) of the product.
What does the top number on the orange panel mean?
It is the Kemler Code, which describes the type and intensity of the hazard.