Why is the fire truck red?

First, red is more conspicuous, similar to the color of fire, and it is easy to attract attention on the road, so that other vehicles can avoid it and it is easier to complete the task.

Second, the first fire truck in the world was red, because red paint was the cheapest at that time, so it continued.

Third, red will make people feel anxious, and whether it is a fire truck, a fire extinguisher or a fire hydrant, their appearance is red, so people will feel nervous psychologically.

In fact, the reason why the fire engine is painted red is that I hope other cars will get out of the way immediately after seeing the red fire engine, so that the fire engine can go first and put out the fire as soon as possible. Of all the colors, red has the longest wavelength, so it can be seen from far away. The reason why traffic lights stop red is also based on this truth.

Among the seven-color rainbows, the longer wavelengths are red, yellow and green. Our eyes have cells that can distinguish red, green (yellow) and blue. Because there are more cells that can see red, red looks conspicuous.

Moreover, red can stimulate our visual nerve, which means warning, making us aware of danger and making us nervous. Therefore, it is most appropriate to use red to indicate stop.