Malloy Milling grinds calcined alumina to a standard granular size. The mill produces two different size products, regular grind and super grind, from the same raw materials. After reviewing the production data, the company found that the regular grind product has an average particle size of 100 microns with a standard deviation of 5 microns, while the super grind product has an average particle size of 80 microns with a standard deviation of 3 microns. What is the difference in particle size between the regular grind and super grind products?