What is the accordion effect and how can it be avoided in traffic jams?

Have you ever wondered what the accordion effect is and how to avoid it? First of all, let’s recall that this effect usually occurs during traffic jams due to an excess of cars in a given stretch of road. As the Directorate-General for Traffic has stated, “many traffic jams occur due to a chain reaction that happens when something on the road causes traffic to slow down, but then, because this effect is not taken into account, the waiting time keeps building up from vehicle to vehicle until the jam becomes much larger than strictly necessary”.

Therefore, after a sudden stop, “traffic resumes with more delay the further back you are in the queue. After the first car starts moving, the second takes an extra second; the third adds another second to the previous one (1 + 1) and so on… The visual effect is that the line of vehicles stretches like an accordion,” as the DGT has added.

This is how the Directorate-General for Traffic explains the accordion effect

After a stop or a sudden braking, traffic resumes with more delay the further back you are in the queue.

The visual effect is that the line of vehicles stretches like an accordion🚗 🚕 🚙 🚗.

Find out why it happens and how to avoid it.

👉https://t.co/AQyZtwdxgY#CeroRiesgos pic.twitter.com/nrOsikJTq1

— Dir. Gral. Tráfico (@DGTes) May 24, 2022

Likewise, Traffic points out that “for example, in a line of 2,000 cars – stretching 12 to 16 kilometres long – the last vehicle could take up to 30 minutes to start moving.” “If drivers are not attentive, it takes longer than necessary to start moving, and drivers behind in the tailback experience a multiplied waiting time.”

Now that you know what the accordion effect is, which causes major traffic jams, the Directorate-General for Traffic advocates that drivers practise preventive driving, anticipating what may happen. In this way, the possible negative effects of traffic queues will be minimised.

A safe following distance must be maintained at all times to be able to react with sufficient advance notice. “Waiting until the last moment to brake causes sudden braking.” For this reason, the DGT recommends not accelerating and driving at gentle speeds, even tapping the brake pedal to warn other road users, since “the disparity in speeds fosters the accordion effect, whereas a uniform speed among those sharing the road increases fluidity,” the DGT concluded.