While weathering steel works well in arid environments, or in environments where the steel can dry out after it becomes wet, environments that are constantly wet or contain chemicals (e.g., deicing materials) deteriorate the patina layer, causing the steel to lose section. To combat this, portions, or all weathering steel members subjected to unacceptable conditions are coated (frequently brown to match the color of the weathering steel) to help prevent accelerated deterioration. In this case, preparation of the weathering steel by abrasive blast cleaning is recommended; however, references to the SSPC surface cleanliness standards may still not be appropriate. Rather, the specification should describe the intended level of cleanliness (e.g., removal of all visible mill scale & rust approximating SSPC-SP10, and a minimum/maximum surface profile depth). A zinc rich primer or barrier-type high solids epoxy primer with an epoxy intermediate, and a polyurethane, polysiloxane or fluorourethane finish coat will help prevent deterioration of the weathering steel substrate. Multiple coats may be required If the weathering steel is badly pitted from exposure. A KTA University article written by Bruce Rutherford (published to the site in January 2018) describes the challenges and possible approaches for measuring surface profile on pitted weathering steel after abrasive blast cleaning.