To avoid hazards with fog, caution and some precautions are necessary, such as reducing speed and adjusting safety distances.
High pressure in the cold season has the effect of forming fog , atmospheric humidity condensed into microscopic water droplets that remain suspended in the air, giving rise to the infamous “white wall”. It is one of the conditions most feared by motorists as it significantly worsens visibility, considerably straining the eyes, and makes the road surface slippery. A series of precautions are therefore necessary to avoid unforeseen events with sometimes dramatic consequences. So let’s see some rules of conduct to be observed in case of limited visibility.
- Moderate speed (50 km / h with visibility less than 100 meters).
- Increase the distance to the vehicle ahead – you barely have to see its lights.
- Maximum concentration: no chats or mobile phones. The radio should also be kept at a low volume so as not to block out external sounds.
- Fog wets the windshield: remember to operate the windshield wiper from time to time.
- Keep the air conditioner on to prevent the windows from misting up.
- When maneuvering, in parking lots and even at intersections, open the windows a little: in the fog it is more important to hear the approach of other vehicles.
- In these conditions the eyes get tired: make more frequent stops to let them rest.
- The fog is usually thicker at night and at dawn, and clears between 12 and 15. Take this into account if you have to plan a trip.
- Before leaving, find out about the traffic conditions; in your car, listen to the news on the radio.
EYE IN THE REAR FOG
The rear fog light must be turned on when bad weather conditions (including heavy rain or snow) reduce visibility below 50 meters; Article 153 of the highway code says so, which prescribes the same indications for the use of fog lights. If the view is good, these lights are forbidden: remember to turn them off as soon as the white “wall” thins out, so as not to dazzle others. If your car does not have fog lights, use the low beams (never the high beams) by lowering the light beam to the maximum (usually, the control is on the left side of the dashboard). Keep in mind that modern xenon or LED headlights are often equipped with a function for “adverse atmospheric conditions”, which can be activated with a button: the light beams are lowered and made more “horizontal”, so as to transform them into lights “from fog”.
Modern electronic driving aids also work in fog , but those that rely on cameras (such as lane keeping systems and automatic emergency braking) cease to perform well (or indeed work). Even with the most equipped car, maximum caution. When the fog wets the windshield, it is better to activate the “wipers” by hand: the automatism reacts late.
On the motorway, there are specific signs ( here on the left ) that help us to evaluate the intensity of the fog based on visual indicators shown on the asphalt. If only one sign is visible, moderate your speed to no more than 40 km / h, if two signs are visible no more than 60 km / h.