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Turvallinen ajonopeus on tärkeää

Safe driving speed

In addition to speed limits, the choice of safe speed is influenced by the condition of the road, driving conditions, visibility, vehicle load, nature of the cargo and traffic conditions. The speed must be kept such that the driver will maintain control of the vehicle and can stop it, if necessary, even in poor weather.

Speed limits increase safety and assessment possibilities

Studies have shown that it is always difficult to estimate the speed and distance of an approaching vehicle. In general, the speed of the approaching vehicle is estimated to be lower and the distance greater than they actually are.

Speed limits are also an important factor in the safety of pedestrians and cyclists. Low speed limits – and obeying them – are an important safety factor, especially in areas where there are many pedestrians and cyclists, and where there are many zebra crossings without traffic lights. An effective way to improve the safety of zebra crossings is to reduce vehicle speeds. It reduces the risk not only of accidents but also of serious injuries. 

The maximum permitted speed is not always the same as a safe speed. If the conditions, traffic environment or traffic situation make driving more difficult, it is best to reduce speed.

At a lower speed

  • you have more time to make observations
  • the stopping distance and time are reduced
  • control of the vehicle improves
  • the consequences of a collision are less severe
  • the car’s safety technology is more useful.

Time saving at different speeds

There is usually always a reason for using a speed below the speed limit, and it is a good idea to get used to it in traffic.

How much time do you lose over a 10 km distance if you have to drive 80 km/h instead of 100 km/h? Just a minute and a half.

Even minor changes in vehicle speed affect road safety.

Speed increases impact force

The vehicle collision energy is quadrupled when the collision speed doubles. For example, if a vehicle collides at a speed of 50 km/h with an obstacle that will not deform or move away, or with another vehicle from the opposite direction at the same speed, the impact force caused by a person weighing 80 kg and affecting the person is 3,000 kg. Correspondingly, if the impact takes place at a speed of 100 km/h, the impact force is 12,000 kg.

At higher collision speeds, the chances of humans surviving greater decelerations are reduced. In addition, the higher the collision speeds, the less likely the vehicle and its safety devices are to protect people.

The collision speed determines the possibilities of pedestrians surviving. The probability of death increases sharply when the collision speed exceeds 60 km/h.

The basic problem with zebra crossings is too-high speed limits. In terms of pedestrian safety, the difference between 30 km/h and 40 km/h is drastic.

A quarter less speed – the braking distance is reduced by almost half

The stopping distance of a vehicle consists of the reaction and braking distance. In a sudden situation, a driver usually takes at least one second from recognising a hazard to pressing the brake pedal (reaction time). For example, at 100 km/h, the vehicle will travel 28 metres in one second. The braking distance is approximately 43 metres from this speed in good conditions. This means that it will take about 70 metres to stop the vehicle.

The vehicle’s speed directly affects the braking distance. As the speed doubles, the braking distance is quadrupled. The converse is also true: reducing the speed by one quarter shortens the braking distance by almost half.

Winter speed limits

Winter speeds are also always about the speed limits during the dark season. The aim of reducing speeds is to reduce the risk of accidents due to seasonal fluctuations. The limits from summer speeds to winter speeds are often changed in October to November due to dark and slippery night conditions.