The ADR Plate, Hazchem & ADR Vehicle marking all come under the European Agreement Concerning the International Carriage of Dangerous Goods by Road regulations – ADR.


In the UK, the Hazchem Emergency Action Codes (EAC) must be used. This system of marking must not be confused or combined with international ADR marking, which uses Hazard Identification Numbers (HIN), also known as the Kemler/Kemmler Code, which all other vehicles must use.

Emergency Action Codes (EACs), also known as Hazchem codes, are a three character code that must be displayed on all GB registered road and rail vehicles that carry dangerous goods on domestic journeys within the UK.

The ADR plate below shows the EAC in the top section and the UN Number (which identifies the substance) at the bottom.

ADR Plate ADR panel image

EACs provide a quick assessment to the emergency services of what actions should be taken during and accident. The fire and police services use the specific characters and numbers to determine which actions may be necessary, during the first few minutes of an incident involving dangerous goods.

EAC’s are characterised by a single number (1 to 4) and either one or two letters (depending on the hazard).

The AEC is interpreted by the Emergency Action Code pocket cards, the latest version of which is shown below.

EAC Emergency Action Code List image


The ADR Hazard Identification Number HIN, also known as the Kemler Code, is carried on road and rail vehicles with tanks etc carrying bulk loads of dangerous substances.

The ADR plate below shows the HI Number in the top section and the UN number (which identifies the substance) at the bottom.

ADR Plate adr panel image

The HI number consists of two or three figures. The first figure of the Kemler Code indicates the primary hazard, the second and third figures generally indicate secondary hazards. Doubling of a figure indicates an intensification of that particular hazard. Where the hazard associated with a substance can be adequately indicated by a single figure, this is followed by a zero.

If a hazard identification number is prefixed by letter ‘X’, this indicates that the substance will react dangerously with water.

Both the EAC and HI numbers are published every year in the NCEC’s Dangerous Goods Code Emergency Action Code List.


Placarding refers to the ‘hazard warning diamonds’ that are required for tankers carrying bulk quantities of hazardous substances and other vehicles carrying class 1 or class 7 goods in packages. Placards are 250mm square and must be displayed according to the type of load.  The smaller (100x100mm) warning diamonds are specifically for labelling packages and should not be used on vehicles.

Marking refers to the plain orange ADR plate carried at the front of vehicles (and on the back of vehicles carrying packages). It also refers to the other marks (such as the (EHS) Environmentally Hazardous Substance mark, which are required, where appropriate, on the back and sides of vehicles.

ADR allows the familiar plain orange ADR plate to be divided by a horizontal black line.


Vehicles carrying packages of dangerous goods must display the plain orange ADR plates, as described in ADR at A plain orange plate must be fixed at the front and back of the transport unit. There is the extra requirement for vehicles carrying class 1 (explosives) and class 7 (radioactive substances) to display placards on both sides and the rear of the vehicle.




This is similar to the above, but in this case the freight container should display relevant placards (hazard diamonds) on all four sides of the container.

ADR Plate adr panel placard on container


Different requirements apply to GB domestic journeys and international journeys.


GB registered vehicles on GB domestic journeys must be marked with the EAC and include a telephone number for advice in the event of an emergency. The requirement to display the plain orange plate at the front of the vehicle is the same as for packaged goods vehicles.

Plus EHS Mark (where appropriate) on both sides and rear.

EHS mark Environmentally Hazardous Label image


Vehicles with tanks etc on international journeys must show the HI Number (Kemler Code) in addition to the other relevant marks and placards.

ADR Plate ADR panel image

ADR Plate (ADR Panel)

The ADR plate should be displayed at the rear and both sides, with a plain orange plate at the front. Where one substance only is carried it is permissible to display plates at front and rear only, provided the front plate also carries the HI Number and UN Number. Under ADR there is no requirement to display a telephone number.


To BUY ADR Plates, ADR Panels or Hazchem ADR vehicle marking, just visit Stock-Xpress or tel: 0113 203 1942 for enquiries.