Every year at our State Fair I get a rash on my legs that am told is sensitivity to calcium chloride. How do treat it?

There is no known sensitivity to calcium chloride. There are many reports of skin irritation from exposure to large amounts of calcium chloride, but these reports are associated with exposure to powdered forms of calcium chloride. I am not aware of any reports of skin irritation from exposure to calcium chloride in the form of a solution, such as the form it is used in to reduce dust and moisture on paved surfaces.