what type of salt is used on roads

Most roads are treated with rock salt , which is just coarse sodium chloride (NaCl) similar to table salt but in larger, unrefined crystals.

Main type of salt on roads

• Rock salt (sodium chloride) is by far the most common de‑icing material used on highways and city streets because it is cheap, widely available, and effective a little below water’s normal freezing point.

• This rock salt is usually mined from underground salt deposits and then crushed into coarse grains before being spread on roads.

Other salts sometimes used

In colder climates or special conditions, agencies may mix or replace rock salt with other de‑icing salts:

• Calcium chloride (CaCl₂) – works at much lower temperatures than plain rock salt, so it is used when it is extremely cold.

• Magnesium chloride (MgCl₂) – often sprayed or blended with rock salt to help it work faster and at lower temperatures, and to reduce how much salt scatters off the road.

• Potassium chloride (KCl) – sometimes used in blends; it is less common on its own and usually added where vegetation or environmental concerns are a priority.

Simple way to remember it

If you see trucks salting the road, you are almost always looking at rock salt (sodium chloride), sometimes enhanced with liquids like magnesium or calcium chloride to improve performance in very cold weather.

Information gathered from public forums or data available on the internet and portrayed here.