Spain's Hazard Light Trick to Prevent Rear-End Collisions 2026

Spain has normalized a small trick to prevent rear-end collisions: switching on hazard lights when approaching a traffic jam. But the DGT (General Directorate of Traffic) is not entirely on board, as its outdated regulations still call for a different approach.

Emergency braking and hazard lights are words that, by pure common sense, we might assume always go together. So much so that not only in Spain have we assimilated that the way to act in a traffic jam is to activate them almost immediately; manufacturers have also been incorporating this into the latest models.

However, the DGT, through the General Traffic Regulations, still asks us to act in a slightly different way—one that has become somewhat obsolete.

Why rear-end collisions are a common problem in Spain

Rear-end collisions are one of the most common types of crashes on Spanish roads, especially now that summer is here and trips multiply. Although there are no official data segmenting this type of accident, claims and insurance experts estimate that 5% of all crashes are rear-end collisions.

They usually have low fatality rates, but those involved can suffer injuries such as whiplash, which often cause problems over time if not treated properly. Rear-end collisions are not usually a major problem in terms of mortality rates, but they can cause serious damage to our cars.

And although without enough safety distance it is difficult to avoid them, drivers have assimilated a way of acting to reduce them.

What drivers usually do: hazard lights on

The most common action in this type of situation is to turn on the hazard lights as soon as we see a traffic jam ahead. This warns drivers behind that we are slowing down abruptly and helps prevent a chain reaction.

This practice has become widespread in Spain and other countries, and many modern cars even activate the hazard lights automatically under heavy braking. It is a simple and effective way to draw attention and reduce the risk of a rear-end collision.

What the DGT regulations say (and why they are outdated)

The General Traffic Regulations still require drivers to use hazard lights only in specific situations, such as when the vehicle is immobilized or when it represents a danger. It does not explicitly contemplate using them while driving to signal a sudden slowdown.

This creates a legal gray area: drivers use hazard lights to prevent accidents, but technically they might be breaking the rules. The regulation has not been updated to reflect modern driving realities and the safety benefits of this practice.

Key takeaways for drivers

• Hazard lights are widely used in Spain to warn of traffic jams and prevent rear-end collisions.
• The DGT's General Traffic Regulations do not explicitly allow this use while driving.
• Rear-end collisions account for about 5% of all crashes in Spain.
• Whiplash injuries from rear-end collisions can cause long-term problems.
• Many modern cars automatically activate hazard lights under emergency braking.

How to reduce the risk of rear-end collisions

Beyond hazard lights, maintaining a safe following distance is crucial. Drivers should always keep enough space to stop safely if the car in front brakes suddenly. Additionally, paying attention to the road ahead and anticipating traffic jams can help you react in time. The longer history behind the story is traced in Spain's Hazard Light Trick to Prevent Rear-End Collisions.

Using hazard lights wisely—only when necessary to warn others—can complement safe driving practices. However, it is important to be aware of the legal framework and use them appropriately. The background to this story is set out in Colorado Wildlife Overpass Cuts Vehicle-Animal Collisions by 91%. A related thread runs through Sydney Airport Near Misses Spark Urgent Air Traffic Safety Review. Earlier coverage in Sydney Air Traffic Controllers Warn of Collision Risk in Airspace shows how the argument developed.

Comparison of hazard light usage across countries

What to watch next

The DGT may need to update its regulations to align with current driving practices and technological advancements. As more cars come equipped with automatic hazard light activation, the gap between regulation and reality will become more evident. A closer look at the same subject appears in Car: latest articles. Anyone following the wider picture can start with Spain's New Traffic Rules: E-Scooter Age Limit, Cyclists and Motorcycles. The same theme surfaces in DGT Traffic Map: The Most Reliable Road Tool for Spain, which takes a different angle.

Drivers should stay informed about any changes to traffic laws and continue to prioritize safety. Using hazard lights to prevent rear-end collisions is a sensible practice, but it is always advisable to follow the law and drive defensively. Context on how this played out before sits in Volvo EX60 Launches Four New Road Hazard Alerts for Safer Driving. A companion piece, Western US Heatwave Sparks Wildfire Hazard: Key Risks, approaches the same subject from another angle.