It's 6 o'clock in the morning and you're frantically trying to shovel your driveway and de-ice your car before you have to leave for work. Before you run back inside to finish your now-cold cup of coffee and scarf down a quick bowl of cereal, you throw some ice melt onto your sidewalk and driveway so the rest of your family members don't slip as they head out to school and work. With everything else on your plate this morning, you probably haven't really thought about that ice melt outside of, thank goodness we have some in the garage.
You're certainly not alone. Besides, what difference does it make? When the meteorologists are predicting an ice storm, you just grab whatever's on sale--or whatever's left in the store after everyone else picked through the inventory. Anything will work, right? It's all the same, anyway...
Unfortunately, that's not necessarily true. Which deicer you should actually use is dependent upon a number of factors, and one of them is safety. So maybe it's time to take a look at your ice melt before the next big storm hits.
Choosing the Right Deicer
There are some basic things you should take into consideration when choosing the best ice melt for your needs: the surface(s) you want to treat, secondary impact, cost, and safety.
Different surfaces react to various ice melts differently. For example, did you know that chloride-based deicers shouldn't be used on wooden decks? The brine could attract more moisture into the wood and cause it to refreeze, creating black ice. It could also attack the fastening system holding your deck together. So rock salt on wood is our first big no-no.
After considering the surface you want to treat, it's important to look at the surrounding environment, too, and consider the collateral impact. Where will the runoff go? If the area is near a waterway or wetland, for example, excess salt can have a detrimental impact on the ecosystem. It can also affect drinking water supplies if you're near a well or reservoir.
And obviously we all want to make sure we're getting good value, so keep in mind cost per pound when considering ice melt (especially among deicers with the same chemical ingredients).
The 5 Common Deicers
While there are (at least) hundreds of different ice melts on the market today, the truth is that a majority of these products are made using one of 5 different chemicals:
Sodium Chloride (NaCl)
This is the one commonly called rock salt and is probably the most well-known deicer because it is cheap, readily available, and can be found all over the world. Rock salt will melt snow and ice at temperatures as low as 16°F, although it performs best at temperatures in the mid-20s. One problem you might notice with rock salt is staining around the house, or even on your shoes. Since the chemical composition of rock salt is about 67% chlorides and 30% sodium, it's not particularly safe for the environment or pets.
Magnesium Chloride (MgCl2)
Magnesium chloride is very effective at efficiently melting ice. Like sodium chloride, it is found throughout the world. It's slightly more expensive than rock salt but is cheaper than calcium and potassium chlorides. As an ice melt, it is composed of approximately 34% chlorides and 18% Magnesium. It tends to be safer for the surrounding environment, including surfaces and vegetation, and has low toxicity, although those with children or pets should still be careful, as with any ice melt. Commercially it is available in pellet, flake, and liquid solutions and will effectively melt snow and ice down to -13°F.
Calcium Chloride (CaCl2)
Calcium chloride is the most well-known deicer (apart from rock salt) and has been widely used for over 100 years. It is more expensive than the other options above, but its temperature range is lower and can melt ice down to -25°F. It is available in pellet, liquid, and flake form. Despite its premium ice melting capabilities, it has the highest toxicity, tends to be harder on surfaces, and causes salt stains.
Potassium Chloride (KCl)
Potassium chloride isn't used too much as a deicer these days. The benefit of using this to melt ice is that it is environmentally friendly; however, the downsides to this type of ice melt have mostly replaced it in the market, so you likely won't see too much of it. Made of 60% potassium and 37% chlorides, it's inefficient at melting ice because it doesn't melt below 25°F. It is also very expensive compared to other deicers.
Acetates
Acetate deicers commonly found include sodium acetate, magnesium acetate, and potassium acetate. Because they are not chloride-based, they don't cause chloride damage like the other types of deicers mentioned above. Because they are organic chemical compounds, they break down naturally in the environment and have very little impact. These deicers are available in both liquid and dry forms and tend to be used in places where chlorides are banned due to potential corrosion (such as airports and parking garages). These products are more expensive because the ingredients to make them are costly.
Others
There are a number of other types of products that make up the remaining ice melt market. Some of these include Urea, Glycols, Modified Crystalline Carbonyl Diamide, ammonium sulfate, and Calcium Magnesium Acetate. These may be safer for the environment but tend to cost more and work less effectively.
Pet Safety
If you have a pet that goes outside, such as a dog or cat, you might want to be more mindful about what kinds of ice melt you're using, as some may be harmful, particularly if ingested.
If you walk outside in the winter, you're going to put on a pair of shoes; most dogs, however, walk around with unprotected paws (though dog boots do exist!). Winter can be quite ruff on an animal's paws, and two things you want to be mindful of are ingestion and dry paws.
Because animals clean their own paws (and sometimes dogs eat things they shouldn't), you'll want to limit their exposure to salt and ice melts so they don't accidentally ingest something toxic. And while it's unlikely your pet will ingest enough rock salt to make him or her really sick, according to the ASPCA, ingestion of high amounts of ice melt “can potentially produce effects such as drooling, vomiting, diarrhea, loss of appetite, vocalizing/crying, excessive thirst, depression, weakness, low blood pressure, disorientation, decreased muscle function and in severe cases, cardiac abnormalities, seizures, coma and even death" (www.aspca.org). Ice melt can also get lodged in your pet's paw pads and cause burns.
To best protect your furry family members, look for safer ice melts to use. But look at the ingredients and not just the advertising, to see if it is actually safe. Keep in mind that your neighbors and your community might not be using pet-safe ice melts. In these instances, you can add extra protection to your dog by investing in some paw protective balm (some people also use petroleum jelly), booties, or thoroughly wash your pet's feet and belly when you come inside from your walk--before they start licking. Check out more Cold Weather Safety Tips from the ASPCA here.
If your pet ingests ice melt, it's best to contact your vet right away. You can also call the Pet Poison Helpline (800-213-6680), or the ASPCA’s Animal Poison Control Center (888-426-4435).
Similarly, if your child happens to ingest ice melt, it shouldn't cause problems, but the chemicals can cause irritation. In the event of ingestion, wipe out your child's mouth, give a small glass of milk or water, and wash their hands and face. Then you can call Poison Control (1-800-222-1222) or use the webPOISONCONTROL® online tool for guidance.
Sources:
http://meltsnow.com/the-right-ice-melter.htm
http://www.ossian.com/petsafe_doc.htm
http://www.poison.org/articles/2010-dec/ice-melt-products-harmful-to-pets-and-kids
http://www.dogsnaturallymagazine.com/finding-paw-friendly-ice-melt-products/
