DUST BINDING SALTS

The purpose of dust binding gravel roads is to keep the moisture in the road surface. Two salts are useful for this. If the relative humidity is more than about 35% they absorb moisture.

You can spread the salts as dry "Flakes" or you can dissolve the flakes in water and spread as a brine. Both salts have a better effect if they are spread as a brine.

Magnesium chloride has about 30% less effect than calcium chloride. If spread as flakes Magnesium chloride turns into solution faster then calcium and therefore penetrates into the road surface quicker. Furthermore, the magnesium chloride is not classified as irritating, which makes it useful on riding arenas and paddocks.

Since it has a slightly lower efficiency, the dosage recommendations are usually 30% higher than for calcium chloride but the price is about 30% lower. The final effect is thus comparable between the salts.