Try our tool below to assess your ISO9223 C1 through C5 and CX environments. These scores are based on a variety of environmental conditions, including temperature, relative humidity, atmospheric sulfates, and atmospheric chlorides. For simplicity, we break them into half increments, so a C1.5 environment is between a C1 and a C2, but closer to a C2 environment. For full detail on this map and product, please read our blog post on our ISO9223 Product! (will open in a new window). ISO9223 data was updated as of 11/30/2024 to reflect trailing 5-year averages (2019–2023). Additionally, Zinc corrosion rates (µm/year) updates have now been included.