We have already had our first snowfall and I had to retrieve my snow shovel from the shed. In the process of getting out my winter tools, I had trouble finding the salt for the sidewalks and driveway. To my surprise last years’ bucket of salt changed to salt water. Can’t use that on the driveway! So, I needed to make a trip to the local hardware store. I forget, do I buy rock salt or calcium chloride? So I went to the Internet to look up the differences. Back in the old days when I was growing up, we had only rock salt and the shovel. Now, we have so many choices and much more information. Dr Anna Marie Helmenstine Ph.D. writes an article on about.com to explain the differences. But here’s a brief description of what I found the differences to be:
Sodium Chloride (Rock Salt or Halite):
Sodium chloride is inexpensive and helps keep moisture from accumulating on roads and walkways, but it is not an effective deicer at low temperatures (only good down to -9°C or 15°F), damages concrete, poisons the soil, and can kill plants and harm pets.
Calcium Chloride works at very low temperatures (-29°C or 20°F) and isn’t as damaging to the soil and vegetation as sodium chloride, though it costs a bit more and may damage concrete. Calcium chloride attracts moisture, so it won’t keep surfaces as dry as many other products. On the other hand, attracting moisture can be a good quality since calcium chloride releases heat when it reacts with water, so it can melt snow and ice on contact. All deicers must be in solution (liquid) in order to start working; calcium chloride can attract its own solvent. Magnesium chloride can do this too, though it isn’t used as commonly as a deicer.
So, after doing some research, learning the differences between Salt and Calcium Chloride, and finding out the environmental impact, I settled for the Calcium Chloride!
9 Eco-friendly ways to De-Ice Your Driveway by: theDailyGreen.com of GoodHousekeeping.com