Rock salt is normally quite course an is sold by the bag for walkways and by the tonne for parking lots. The city of Toronto primarily uses salt for the streets in this form and also by presalting with a liquid brine before a snowfall.
An alternative that we use for clients who want ice control with out as many downsides is magnesium chloride pellets. Its much less toxic then salt and has been compared to baking soda in its level of toxicity. MAG ice melting pellets contain a third less amount of chlorides then either calcium chloride or salt. This translates into less harmful chlorides going into our waterways.
MAG is very easy to handle and will not burn or irritate skin or pets paws. It works at a lower temperature then salt and does not leave an oily residue like calcium chloride that can track into your home or business. Its also causes less damage to concrete.
Calcium Chloride is a powerful ice melter that works at a very low temperature. It is not considered an alternative to salt from an environmental perspective but because of its very low melting temperature it would be effective during a deep freeze when salt would not work.
Calcium Chloride is not as friendly to the persons spreading the product as it is slightly irritating to skin and care must be taken not to breath in the dust.
Our preferred product from a performance and environmental impact is by far the Mag ice melter. Keep in mind however that even this product should not be used with out care as it still contains chlorides (not as much as salt) which do have a negative impact. Also its shipped all the way from the Dead Sea. Its important to use just enough to make your property safe and not over apply.
To obtain a ice melter that is non corrosive and even less toxic then the ones shown here would be sodium acetate. Its used at airports because its non corrosive and biodegradable. Acetates contain no chlorides. These are much more expensive however.
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