Do you know how many centimeters a car should be flooded out due to a typhoon or guerrilla rainstorm? Explanation by degree | MOBY [モビー]

Do you know the effect of the degree of inundation?

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If a large amount of rain falls in a short period of time due to a typhoon, etc., the rainwater may not be drained completely and may be flooded depending on the location.

Depending on the degree of flooding, even a heavy car may be washed away. But did you know that even a small amount of flooding can be dangerous?

In this article, we will explain “how many centimeters of water will affect a car” in three major stages.

[Water depth of about 30 cm]There is a possibility that the muffler will be flooded and will not move.

Image image when flooded to a depth of 30 cm

If the water depth exceeds the floor surface, there is a risk that the vehicle will be flooded and the electrical equipment will be damaged, or that the muffler will be flooded and the engine room will be damaged.

As a result, problems such as “automatic sliding doors and power windows do not work” and “engines and motors stop and cannot be restarted” may occur.

In electric vehicles (BEVs) and hybrid electric vehicles (HEVs, PHVs), the vehicle may stop if the drive battery is flooded.

[Water depth about 50 cm]The door may not open

Image image when flooded to a depth of 50 cm

When the water depth reaches the lower end of the door, water pressure is applied from outside the vehicle, making it difficult to open the door from inside the vehicle.

[Water depth of about 100 cm]There is a possibility that the vehicle will float and be washed away.

Image image when flooded to a depth of 100 cm

If the tires are completely submerged, the car body may float and it may be difficult to move. Also, if the water depth exceeds half the height of the door, it will be almost impossible to open from the inside.

When the height of the water flooded inside the car is about the same as the outside, the water pressure difference between the inside and outside disappears, and the door can be opened from the inside.

Also, if there is an escape hammer inside the car, you can evacuate outside the car by breaking the glass of the car with it. However, the windshield and some door glass are laminated glass and cannot be broken. Please check with each manufacturer as the properties of glass differ depending on the model.

You can drive safely up to “floor height”

Source: Ministry of Land, Infrastructure, Transport and Tourism
* The effect of flooding on the vehicle depends on the shape and design of the vehicle. In particular, it is necessary to be careful because it is easily affected by vehicles with low vehicle height.

According to the “submerged road test” conducted by JAF (Japan Automobile Federation), the 2,000cc class sedan was able to run to a submerged waterway at a depth of 30 cm, but the engine stopped at a depth of 60 cm.

30 cm here corresponds to the height of the floor in the above image released by the Ministry of Land, Infrastructure, Transport and Tourism.

Danger changes depending on running speed and the presence or absence of water flow

If the running speed of the vehicle increases even if it is about 30 cm, the water that the vehicle winds up and the waves that are generated may flood the engine from the intake port, and in the worst case, the engine may stop and stop operating.

In addition, if the vehicle height is low or there is water flow, the vehicle may be washed away even at a slight water depth, increasing the risk.

This article explains in detail what to do when the vehicle is submerged.

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