Sand can be crushed by traffic and produce airborne dust, which contributes to pollution. Because sand is easily blown off the road by traffic, it requires repeated applications. It can be very effective for melting black ice and freezing rain. Wetting traditional sanding material with magnesium chloride causes sand to stick to snowpack better. Keeping sand on the road is nearly impossible in some circumstances, especially in very cold weather and in cases where there's traffic at highway speeds.
Magnesium chloride can keep the sand from blowing to the shoulder of the road.
Magnesium chloride is usually the most cost-effective alternative when considering the whole picture. There are less expensive chemicals to use for snow and ice control, such as salt and straight calcium chloride. But those alternatives can be harmful to vehicles, bridges and the environment. Magnesium chloride is a good alternative because it is less corrosive and works better than other chemicals. It reduces environmental impact, bridge corrosion and vehicle damage.