Fog is among the most insidious weather phenomena for every driver, as it drastically limits visibility and turns even a familiar road into a risky route. The main problem when getting into a thick water veil is related to the optical illusion it creates.
Moisture and light scattering distort the perceptions of the human eye, making the silhouettes of preceding cars and obstacles appear significantly further away than they actually are. This false sense of safety critically shortens the reaction time in case of sudden braking.
In severely reduced visibility, maintaining a low speed of about 20-30 km/h and drastically increasing the distance are the first mandatory steps. Choosing the right lighting is also crucial for safety. Fog lights are designed with a wide, low beam that cuts through the thick layer of moisture near the asphalt, rather than reflecting into it.
Turning on the high beam in such a situation is a serious mistake, as the powerful beam is reflected by the water droplets and creates the so-called “white wall“, which completely blinds the driver himself. The rear fog light and hazard warning lights are also extremely useful, since the pulsating orange light is noticed much faster than the standard red indicators by cars approaching quickly from behind.
From a physical point of view, fog not only reduces visibility, but also changes the coefficient of adhesion to the road surface. Microscopic water droplets condense on the asphalt and form a thin, slippery and wet film, which in its properties is similar to light rain or dew. In such conditions, any sudden braking or abrupt lane change can easily cause loss of traction and skidding.
Therefore, smooth steering movements, gradual reduction of speed using the engine brake, and complete abandonment of overtaking are the key elements for preventing chain collisions in conditions of critically poor visibility.