You need backflow protection for your commercial location to protect your drinking water supply. Backflow is the undesirable and potentially dangerous reversal of the flow of water or mixtures of water and other undesirable substances from any source into the distribution pipes of the drinking water system. These unwanted substances can include used water, industrial fluids, gasses, or any substance other than the intended potable water
A good commercial plumber can assess your plumbing system and make recommendations/repairs as needed. You as a business owner must protect your drinking water system and the health of your neighbors, employees, and customers by preventing all cross connections on your premises.