ADR placards - Designations of hazardous materials

What are ADR placards?

ADR placards are plates, stickers, and warning notices that provide information about the dangerous goods being transported. ADR markings provide better protection for both the driver and other road users, as well as the emergency services in the event of an accident.

What is an ADR plate?

The ADR plate is an orange reflective information board with a black border. It is affixed to vehicles transporting hazardous materials. It is valid for road transport in all countries covered by the ADR agreement (i.e. virtually all of Europe, excluding the UK).

The ADR plate comes in two versions:

• With the identification numbers of the substance being transported (used for tanker or bulk transport); 
• Without numbers (used for carriage in parcels).

What are HINs?

HINs are hazard identification numbers. They consist of two or three digits, which you will find at the top (counter) of the ADR plate.

The first digit identifies what type of hazardous material you are dealing with. We can distinguish here:

• Gas (2), 
• Flammable liquid material (3), 
• Flammable solid material (4), 
• Oxidising, fire-supporting or organic peroxide material (5), 
• Poisonous material (6), 
• Corrosive material (8).

As for the second and third digits, they specify the type of hazard, the degree of danger and its additional characteristics. We can distinguish here:

• No additional hazard (0), 
• Explosiveness (1), 
• Gas producing capability (2),
• Flammability (3), 
• Oxidising properties (5),
• Toxicity (6), 
• Radioactivity (7), 
• Corrosivity (8),
• Risk of violent reaction due to spontaneous decomposition or polymerisation (9).

If the digit is repeated (i.e. the first and second digits are the same), this indicates the severity of the main hazard.

In addition, an "X" sometimes appears in the HIN number. If you see it at the beginning, know that the material in question must not come into contact with water under any circumstances.

What are UN numbers?

UN numbers are material identification numbers and refer to a specific substance. Each consists of four digits and can be found at the bottom (denominator) of the ADR plate.

E.g. UN code 1090 indicates that there is acetone in the vehicle.

What are the requirements for ADR markings?

The requirements for ADR markings are as follows:

• ADR stickers - Size at least 10 cm x 10 cm for ADR packages or 25 cm x 25 cm for vehicles; 
• ADR plates - Size 40 cm x 30 cm and height of lettering at least 10 cm;
• UN dangerous goods number on packaging - Size of letters, numbers and symbols at least 12 mm. For packages up to 30 kg at least 6 mm (small packages up to 5 kg may have their lettering reduced accordingly).

What are the ADR markings for specific classes?

ADR markings for specific classes of hazardous materials are represented by ADR stickers, which refer to specific types of hazard.

Hazardous materials marking - Class 1

Class 1 has four separate stickers representing the hazard.

The first (numbered 1) refers to subclasses 1.1, 1.2 and 1.3, i.e. materials posing a hazard of (respectively) mass explosion, projection and fire or moderate explosion/ projection.

The next sticker (with the number G1) refers to subclass 1.4, i.e. materials presenting a minor explosion hazard after ignition or initiation.

The next sticker (numbered D1) refers to subclass 1.5, i.e. materials that are highly insensitive but present a mass explosion hazard.

The last sticker (numbered N1) refers to class 1.6, i.e. materials that are extremely insensitive but do not present a mass explosion hazard.

Hazardous materials marking - Class 2

Class 2 has three separate stickers, one for each subclass.

The red sticker (with the number 2) refers to flammable gases.

The green sticker (with the number 2) represents non-flammable and non-toxic gases.

The white sticker (with the number 2) represents toxic gases.

Hazardous materials marking - Class 3

Class 3 is represented by a single sticker (with the number 3), which includes all flammable liquids.

Hazardous materials marking - Class 4

For Class 4, the ADR agreement provides for three separate stickers, one for each subclass.

The red and white striped sticker (with the number 4) represents flammable solids.

The red and white sticker (with the number 4) represents solids that are capable of spontaneous ignition.

The blue sticker (with the number 4) refers to solid materials that produce flammable gases when in contact with water.

Hazardous materials marking - Class 5

Two stickers have been developed for class 5, which correspond to the two subclasses.

The yellow sticker (with the number 5.1) refers to oxidising substances that are not organic peroxides.

The red-yellow sticker (with the number 5.2) represents organic peroxides.

Hazardous materials marking - Class 6

Class 6 also has two stickers, one for each of the two subclasses.

The white sticker with the skull (and number 6) represents poisonous materials.

The white sticker with the infectious symbol (and number 6) refers to infectious materials.

Hazardous materials marking - Class 7

As regards class 7, there is only one yellow and white sticker (with the number 7), which refers to radioactive materials.

Hazardous materials marking - Class 8

Class 8 also has one sticker in black and white (with the number 8), which stands for corrosive materials.

Hazardous materials marking - Class 9

Class 9, the last, also has one type of sticker which is white with black stripes (and the number 9) to stand for other hazardous materials.

What is a Safety Square?

A Safety Square is a symbol that indicates the level of risk that a substance may pose to health and the environment. You will find it on most shipments from the United States, as it refers to the NFPA system there for rapid threat recognition.

The square consists of four sectors.

The first sector is white and refers to specific types of threat. There are several options here:

• Box blank inside - No additional risks; 
• Crossed out "W" - Substance dangerously reacts with water;
• Radiation symbol - Radioactive substance; 
• OX/OXY - Oxidant; 
• SA - Simple asphyxiating gas; ● Other symbols (unrelated to the NPFA system) also occur.

The second sector is yellow and refers to the explosion potential (i.e. instability) of the material. The hazard level is indicated by the numbers:

• 0 - No danger under normal conditions;
• 1 - Material stable under normal conditions but hazardous when heated or under high pressure; 
• 2 - Material undergoes hazardous chemical reactions when heated or at higher pressure. Also reacts with water; 
• 3 - Material capable of detonating as a result of a strong stimulus (e.g. impact). In addition, it reacts explosively upon contact with water; 
• 4 - Unstable material, capable of exploding even under normal conditions.

The third sector is red and refers to the flammability of the substance being transported. Here too, the threat level is indicated by the numbers:

• 0 - Non-flammable material; 
• 1 - Material requires strong heating to ignite (flash point above 93°C);
• 2 - Medium flammable material (flash point between 38°C and 93°C);
• 3 - Flammable material, capable of igniting under normal conditions (temp. between 27°C and 38°C); 
• 4 - Extremely flammable material at all temperatures.

The fourth sector is blue and refers to the hazard that the substance poses to human health. The threat level is indicated by the numbers:

• 0 - No health hazard; 
• 1 - Material may cause temporary health damage; 
• 2 - Hazardous material causing damage to health with risk of complications; 
• 3 - Highly hazardous and poisonous material; 
• 4 - Extremely hazardous material, even brief contact poses a risk of death or serious poisoning.

What is the Hazchem Code?

Hazchem Code is a warning plate system used in Australia, Hong Kong, Malaysia, New Zealand, India and the UK on vehicles transporting hazardous substances, as well as on storage facilities for hazardous materials. Chemical hoses that meet the required standards are required to transport hazardous materials within both vehicles and warehouses.

The Hazchem Code consists of five parts, which contain the information necessary to undertake a rescue and firefighting operation. These are:

• Hazchem code, 
• UN number (same as in the ADR plate), 
• Manufacturer's or distributor's number where full information on the substance can be obtained, 
• Graphic symbol for the type of hazardous material, 
• Manufacturer's trademark.

As for the Hazchem code, it consists of a digit and one or two letters. The digit refers to the type of extinguishing medium that can be used. Here we distinguish between:

• Compact water current (1), 
• Diffused water current (2), 
• Foam (3),
• Powder (4).

In contrast, the first letter (placed in the second position) indicates the type of personal protective equipment required, together with information on the potential for a violent reaction of the chemical and whether the substance should be doused or diluted.

Each Hazchem code contains at least one of the letters: P, R, S, T, W, X, Y, or Z.

Additional explanation in the table:

• V - Substance may react violently or explode. 
• Full protection - Full chemical clothing + ODO apparatus (independent of circulating air). 
• Breathing protection (ODO) - ODO apparatus + protective gloves. 
• Dilute - Substance may (after considerable dilution) be discharged into the sewage system. 
• Contain - Ensure that the substance is prevented from entering drains or groundwater.

Finally, the last letter of the Hazchem code is "E". If it is present, it indicates the need to evacuate people from the vicinity of the incident. Some organisations recommend that an area within a radius of at least 300 metres should be evacuated.

Additional explanation in the table:

• V - May react violently or even explosively. 
• BA protection - Use breathing apparatus and protective gloves. 
• Full protection - Wear full body protective clothing with breathing apparatus. 
• Dilute - Flush to drain with plenty of water. 
• Contain - Prevent spillage from entering drains or watercourses.

Summary

You already know what ADR markings are and how to read them. In addition, you are familiar with the other types of hazardous material markings that apply in countries not covered by the agreement.

Remember that marking your vehicle and packaging with the correct plates and stickers is regulated by law when you are transporting hazardous substances. Anyone who does not comply with the regulations risks heavy fines.

It is therefore good to know how dangerous goods should be labelled.