The Magic of Road Salt

During the blistering winter months when snow and ice coat the pavement, many folks prefer to keep their cars in the garage and out of harm’s way. Of course, this isn't a feasible option for most working Americans who have to navigate the slippery roads and arrive punctually at their destinations. For such commuters, there is an unassuming hero that drastically improves driving conditions and keeps your tires and shoes planted firmly on the ground. This hero is a simple chemical compound known as road salt.

The Chemistry Behind Ice Melt

Salt, as we know from grade school chemistry class, is formed from sodium and chlorine atoms. This is the same compound that we find at the kitchen table, though table salt is often iodized, meaning it contains iodine. Although it is the same compound, the rock salt made for roads is not to be eaten. Mineral salt is not purified and contains traces of other substances giving it a more brown or gray color. In addition, mineral salt is often mixed with additives such as sodium hexacyanoferrate (II) and sugar to prevent caking when delivered using gritting machines. In a nutshell, road salt reduces the slip by lowering the freezing point of water. The mixture of salt and water simply requires lower temperatures to freeze which is why salt can liquify ice. However, there is a limit. The use of road salt is only effective until temperatures reach around 0-20 degrees Fahrenheit depending on the ice melt. Below that, the ice will remain frozen. Some other compounds can be used effectively at lower temperatures such as calcium chloride with its lowest effective temperature sitting at about -25 degrees Fahrenheit. The downside is that calcium chloride is extremely corrosive and also adds large measures of calcium to soil, raising its pH to unhealthy levels. Salt remains the compound with the largest collective sum of both safety and effectiveness.

Tips for Applying Road Salt to Pavement

When applying salt to driveways, walkways, and roads, there are some things to consider. The first is a preventative measure that can help reduce shoveling time and the overall amount of salt laid. It is called preventative gritting and essentially means to throw down a layer of salt before the snow and ice roll in. This can reduce your efforts by half or more. In the event of an unexpected freeze, it is important to clear all the snow before salting the pavement. This maximizes the salt’s efficiency in melting the ice. Once the snow is cleared, make sure the salt is spread evenly.

A handful of salt for every square yard or so is sufficient for a proper melt. If you have a large property to grit, doing so by hand may be quite the task, consider using a gritting lorry to distribute the salt rapidly and uniformly. Perhaps most important of all is choosing the right road salt. The grain size can dramatically affect the melting process. Smaller grains can sink down more quickly into the slush but lose their effect much sooner than do more coarse grains. Though coarse grains take a bit longer to melt ice, they will keep your drive ice-free for much longer. It is often beneficial to use a combination of small and coarse grains.

At Asphalt Materials, we carry the finest road salts and ice melts for both personal and commercial use. Our road salt type C is perfect for melting ice on asphalt surfaces. Our type C salt is effective in melting ice down to around 0 degrees Fahrenheit and is available in bulk or 50-pound bags. It is no question that if you live in a region where winter snows fall heavily, salt is a good friend to have. Come on over to our website and pick yourself up a bag today!