Prevent your car windows from fogging up

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Prevent your car windows from fogging up

Prevent your car windows from fogging up

The endless fogging of car windows and windshields is a daily annoyance for many people, especially in the winter months when moist body heat accumulates within the vehicle and condenses on glass surfaces. Once a window becomes fogged over, it has to be wiped down to facilitate vision, often with a sleeve or even the driver’s palm as he realizes he cannot see out of the windshield. This leaves unsightly smudges once the window dries, and oftentimes the surface rapidly fogs up once again; therefore, it is best to prevent the fogging before it can occur.

Simple ways to prevent fogging

Window fogging can be prevented in many ways. The easiest and most common of these is to simply turn on the car’s defogger, which sends a stream of warm, dry air onto the windshield and around the interior of the car. This acts as a dehumidifier, removing the moisture from body heat and breath (along with moisture brought into the car by wet shoes or small bits of snow) thus leaving nothing behind to accumulate on cold window surfaces. In the winter, it is often tempting to switch the car’s heater to the “recirculate” option because the resulting air is a bit warmer than air coming from outside. This setting keeps all moisture contained within the vehicle and increases the likelihood of fogging. Instead, the heat should be set to pull in outside air and warm it as it passes by the engine. Together with this, regular and thorough windshield cleaning can also greatly reduce occurrences of fogging, as dust and other particles on window surfaces provide a substrate to which water can easily attach.

Here are some strange, but effective ways

Some other quirky methods can be used to prevent window fog. For instance, a raw potato can be cut in half and rubbed over the window surface. As long as the surface is allowed to dry naturally and without disturbance (i.e. wiping or towel drying), the starchy layer left behind by the potato will create a barrier that prevents fogging. Anti-fog sprays like those sold in sporting goods stores for ski masks and swim goggles are also quite effective, albeit more expensive than a single potato, and it isn’t known if they out-perform the potato. Some automotive stores sell products specifically designed to prevent fogging of car windows, including products made by Rain-X and other brands. Some other unorthodox products can work in a pinch. Mentholated shaving cream smeared on the surface and wiped off will prevent fogging, just like it does when smeared on a bathroom mirror. Dishwashing detergent can be used in a very similar way, because the soap particles naturally repel droplets of water. Non-electric dehumidifiers work just like the larger models used to remove air humidity from homes in the summer, but they are highly portable. A small container of dehumidifier crystals―like those in the packets often found in the bottoms of new shoes or in boxes with new electronics―can also work. In the end, a fogged windshield can be extremely dangerous, so it is important to stop fogging before it begins.