Road salt (also known as de-icing salt or snow salt) is a salt used mainly as an anti-slip agent in winter road conditions, but also to prevent dust and snow build-up on roads.[1] Various kinds of salts are used as road salt, but calcium chloride and sodium chloride (rock salt) are among the most common.[2][3] The more expensive magnesium chloride is generally considered safer, but is not as widely used because of its cost and effect on structural integrity.[4][5] When used in its solid form, road salt is often pre-wet to accelerate the ice-melting process.[6]