A coating system comprising an epoxy coating layer prepared from an epoxy formulation which comprises an epoxy resin; a curing agent with no more than 4.5 wt % free amine based on a weight solids of the curing agent; and an adjacent layer prepared from a non-isocyanate polyurethane formulation wherein the epoxy formulation and/or non-isocyanate polyurethane formulation optionally further comprise one or more additives selected from the group consisting of solvent, reactive diluent, plasticizer, pigment, filler; rheology modifiers, dispersants, surfactants, UV stabilizers, and corrosion inhibitors is provided. Also provided are a method of applying a multi-layer coating system and an article comprising a coating system.