• When the winter snow and freezing rain begins to fall, another winter tradition begins--the salting of our streets and sidewalks. Salt melts ice by mixing with the water to create what is called brine. When salt is added to create this mixture, it lowers the freezing point of the water. Different types of salt are more effective under different weather conditions.
  
  

Magnesium Chloride

• Magnesium Chloride melts ice faster than sodium chloride, but it is less effective in very cold temperatures. It will lower the freezing point to five degrees Fahrenheit (negative fifteen degrees Celsius.) Compared to Calcium Chloride and Sodium Chloride, Magnesium Chloride is considered better for the environment. Magnesium chloride is also less likely to kill surrounding vegetation is less likely to be an irritant if it comes into contact with skin.
  
  

Calcium Chloride

• Calcium chloride also melts ice faster than sodium chloride. It will melt ice in temperatures as low as zero degrees Fahrenheit (minus eighteen degrees Celsius.) It is also considered a good choice if you are concerned about ice damaging your walkway, as calcium chloride does not attach to concrete, thus resisting the risk of a cracked walkway.
  
  

Sodium chloride

• Sodium chloride is also known as rock salt or halite. It is the most common sidewalk salt used. While it is not as fast as Calcium chloride of magnesium chloride, it tends to be the more economical choice and also has a slower evaporation pace, so it lasts longer. Sodium chloride works at temperatures of fifteen degrees Fahrenheit (minus nine degrees Celsius) and above. It also has the added benefit of evaporating moisture, which keeps walkways dry. However, it can be corrosive to metals, it can damage lawns and vegetation, and it will leave a white residue upon evaporation.
  
  

In Summary

• If you are using salt by itself, sodium chloride or magnesium chloride are the fastest melters. However, they tend to cost more and typically aren't necessary if you live in a climate where the temperature seldom drops below their freezing points. Choosing a deicer that is appropriate for your climate will help you make a selection that gets the job done without breaking your budget unnecessarily.