When transporting dangerous goods, a roadside inspection may identify non-compliance that must be rectified before the journey can continue and, in certain cases, may lead to the vehicle being immobilised.
For a company operating ADR tanker trucks, knowing which aspects may be checked is not simply a matter of regulatory compliance. It is also part of planning every transport operation.
In February 2026, Spanish legislation governing risk-based inspections and checks on the road transport of dangerous goods was updated, incorporating amendments introduced at European level into Spanish law. The resolution establishes different categories of infringements and identifies situations that may pose a particularly significant risk during transport.
But what can prevent an ADR tanker truck from continuing its journey?
1. A tank that does not meet the applicable requirements
Tanks used to transport dangerous goods must comply with the technical and type-approval requirements applicable to the goods and the type of transport concerned.
Using an unsuitable tank, one that has not been type-approved where required, or one that does not meet the applicable conditions may result in a serious infringement during an inspection.
Inspection regulations expressly identify the use of unsuitable or, where required, non-type-approved tanks, vehicles or containment equipment as situations involving a higher level of risk.
Therefore, before loading, it is not enough to check that the vehicle is available.
The vehicle and tank must be suitable for the goods they are intended to carry.
2. Overdue inspections or tests
ADR tanks are subject to various inspections and tests throughout their service life.
The dates of these checks must remain within the periods established by the applicable regulations.
Spanish inspection regulations classify failure to comply with inspection and test deadlines, or with the permitted periods of use for tanks, vehicles and other containment equipment, as a risk-related issue.
This makes the management of inspection dates an operational priority.
A check left until the last minute can ultimately affect vehicle availability.
3. Missing mandatory equipment
The vehicle must carry the equipment required under the ADR and the written instructions.
Failure to carry the required items on board is also expressly identified as a risk-related infringement in dangerous goods transport inspections.
Pre-departure checks should therefore cover the vehicle’s equipment as well as its documentation.
4. Incorrect hazard marking and signage
Orange-coloured plates, hazard placards, labels, marks and other signage identify the risks associated with the goods being transported.
Missing signage, incorrect positioning or the use of markings that do not correspond to the load may result in an infringement during an inspection.
The updated regulations specifically identify incorrect labels, hazard placards, orange-coloured plates, plates, signs or any other markings on tanks, vehicles and other containment equipment as a risk-related issue.
In other words:
It is not enough for the vehicle to display hazard markings. They must be correct for the operation being carried out.
5. An improperly closed tank
In dangerous goods transport, closure systems play an essential role.
Inspection regulations include failure to close tanks, vehicles, containers or packages correctly among the risk-related issues, including where they are empty and uncleaned.
This last point is particularly important because an empty tank is not automatically exempt from certain obligations.
An empty tank may still be subject to ADR requirements
The ADR covers empty, uncleaned and ungas-freed tanks under certain transport and marking requirements.
Consequently, completing an unloading operation does not necessarily mean that all transport-related obligations have ceased to apply.
6. Failure to comply with filling requirements
Filling a tank does not simply involve loading a particular quantity of product.
The degree of filling must comply with the conditions established for the goods and the type of tank.
Spanish inspection regulations expressly identify failure to comply with the provisions governing the degree or level of filling of tanks as a risk-related issue.
In addition, specific obligations apply during loading and unloading to prevent overfilling and dangerous releases. The loader must check the weight or volume loaded and the degree of filling.
7. Missing or incorrect transport documentation
Documentation is another essential element of any ADR operation.
The consignor must provide the carrier with the necessary instructions and information and, where applicable, the consignment note and other documents required under the ADR.
Before transport begins, it is therefore advisable to check that the documentation accurately reflects the goods, vehicle and planned operation.
A documentary error can become an operational problem when the vehicle is stopped for a roadside inspection.
8. Dangerous goods without the required identification
Identifying dangerous goods is essential to ensure that the authorities, emergency services and other parties involved in the transport chain can understand the risks associated with the product.
The classification, UN number, proper shipping name and all other required information must therefore be consistent with the goods being transported.
In an ADR operation, the goods, documentation and hazard markings must all tell the same story.
9. Failure to meet the requirements applicable after unloading
Unloading does not always mean that a tank is immediately ready to carry any other product.
Since 1 July 2026, significant amendments to the Spanish rules governing the internal cleaning, degassing and depressurisation of tanks used to transport dangerous goods have applied. Among other provisions, Royal Decree 186/2026 establishes the need for internal cleaning before certain inspections, when changing to an incompatible product and before certain repairs or modifications.
After cleaning, the tank must also be checked to ensure that it is clean and empty, and the cleaning facility must issue a certificate containing the relevant information.
Planning the period between unloading and the next loading operation is therefore also part of ADR tank management.
10. Failure to account for traffic restrictions
Not every issue affecting ADR transport is related to the physical condition of the vehicle.
Applicable traffic restrictions and route requirements must also be taken into account.
Traffic regulations establish specific restrictions for certain vehicles carrying dangerous goods displaying orange-coloured plates and provide for designated routes for these transports.
In addition, exceptional circumstances, such as adverse weather conditions or the activation of special civil protection plans, may lead to temporary restrictions on ADR vehicle movements and require vehicles to be parked in safe conditions.
Planning an ADR route therefore involves more than calculating mileage and driving time.
It is also necessary to check where the vehicle is permitted to travel and under what conditions.
The best way to prepare for an inspection is to get ready before departure
A roadside inspection should not be the moment when a company discovers that an inspection has expired, that equipment is missing or that the documentation does not match the operation.
Prevention starts before departure.
Dangerous goods transport requires every operation to coordinate the goods, tank, vehicle, documentation, equipment and route.
For international transport, companies must also consider the specific requirements of the different countries through which the vehicle travels.
At Fernández Aedo, we work in road freight transport, including the carriage of chemicals in tankers and operations between Spain and France.
Because in ADR transport, reaching the destination starts long before the truck takes to the road.