ADR

What is ADR?

The current edition is ADR 2025, which has been in force since 1 January 2025. The regulations are updated every two years by the United Nations (UNECE). This keeps transport regulations in line with new safety insights and technological developments. Vehicles covered by ADR are therefore subject not only to rules on transport documents and marking, but also on the technical design of the vehicle.

Here the electrical installation plays an important role. After all, lighting, cabling and connectors must function safely under a variety of conditions. In our extensive article on ADR lighting and regulations, you can read how these requirements are applied in practice for transport vehicles.

What are ADR's requirements for electrical installation?

Part 9 of the ADR Agreement sets out the technical vehicle regulations. Among other things, it stipulates that a vehicle’s electrical system must be designed and protected in such a way that, under normal operating conditions, no accidental ignition or short circuit can occur.

This means that cables, connections and electrical components must be suitable for the conditions in which a vehicle operates. Consider vibrations during transport, moisture and dirt on the road, temperature differences and mechanical stress on cables. In addition, electrical circuits must be well protected against damage and correctly fused.

In certain vehicles, electrical systems must also be able to be quickly de-energised via a clearly marked control in the cabin. This prevents electrical systems from pose a risk when working with hazardous substances.

What does ADR mean for vehicle lighting?

ADR does not simply prescribe that a light must be "ADR-certified". This is because the regulations assess the vehicle and the complete electrical installation, not one individual lighting product.

In practice, this means that lighting must function reliably within the vehicle's total electrical system. Components must withstand harsh conditions such as vibration, moisture and intensive use. Especially for vehicles used intensively in logistics and heavy transport, a robust lighting system is essential. In the article on lighting for heavy transport, for example, you can read which factors play a role in choosing reliable vehicle lighting.

For electronic components, regulations around electromagnetic compatibility also play a role. Many vehicle lights are therefore also subject to international vehicle regulations such as ECE standards.

ADR, ECE R10 and ATEX: what is the difference?

When it comes to ADR lighting, three regulatory frameworks are often confused with one another. Each has a different purpose:

• ADR regulates the transport of dangerous goods by road, including the design and equipment of the vehicle.
• ECE R10 sets out requirements for the electromagnetic compatibility (EMC) of electrical and electronic vehicle components.
• ATEX relates to equipment for use in potentially explosive atmospheres and is governed by European directives, not by ADR.

ECE standards play a particularly important role in vehicle lighting. The ECE R10 approval specifically relates to electromagnetic compatibility, whilst ADR assesses the vehicle as a whole rather than each light individually.

Why are reliable electrical connections important?

Not only the light itself is important. The cabling and connectors also play a major role in a fault-free installation. This is because poor connections can lead to corrosion, voltage loss or interference in the lighting system.

The electrical connection must also be resistant to moisture and dirt. Many vehicle lighting systems therefore use waterproof Superseal connectors.

These connectors are widely used in vehicle applications as they create a reliable and waterproof connection, withstand vibration and are suitable for tough working conditions. Problems with poor connections or moisture ingress occur regularly in practice. In our article on interference in LED lighting, you can read about what causes this and how it can be prevented.

Which substances are covered by ADR?

The ADR agreement divides dangerous goods into nine transport classes. Among other things, this classification determines how substances must be packed, marked and transported.

The ADR classes are:

1. Explosives
2. Gases
3. Flammable liquids
4. Flammable solids
5. Oxidising substances and organic peroxides
6. Toxic and infectious substances
7. Radioactive substances
8. Corrosive substances
9. Various hazardous substances

Specific transport rules and safety measures apply to each of these classes. These rules determine, among other things, how vehicles are equipped and which safety devices are mandatory.

How often do ADR regulations change?

The ADR agreement is updated every two years. New versions often include changes in transport regulations, documentation requirements and technical regulations for vehicles.

For transport companies, body builders and vehicle manufacturers, it is therefore wise to regularly check whether vehicles and systems still comply with the current regulations. In doing so, it is important that vehicle lighting is also correctly approved. You can read more about this in our article on D-homologation, which explains how type approval for vehicle lighting works.

As a wholesaler of lorry lighting, TRALERT® closely monitors legislation and tailors its product range accordingly, ensuring that our partners always have access to suitable and approved vehicle lighting.

Frequently asked questions about ADR

What does ADR stand for?

ADR stands for the French ‘Accord relatif au transport international des marchandises dangereuses par route’. It is the international agreement governing the transport of dangerous goods by road. Among other things, the agreement regulates packaging, labelling, transport documents and the technical specifications of vehicles carrying dangerous goods.

Is there an ADR mark of approval for a single light?

No. ADR does not approve each light individually, but assesses the vehicle and the entire electrical system. The term ‘ADR lighting’ is primarily a commercial umbrella term. What matters is whether the lighting functions reliably and safely within a vehicle that complies with ADR regulations.

What is the difference between ADR and ECE R10?

ADR regulates the transport of dangerous goods by road, including requirements regarding vehicle design. ECE R10 focuses specifically on the electromagnetic compatibility of electrical and electronic components. Both frameworks may apply simultaneously, but serve different purposes.

View our range of ADR LED work lights here.

View the ADR 2025 edition here