Test stainless steel to see if it needs to be passivated or was properly passivated. These tests detect the presence of iron from fabrication processes, which can limit stainless steel's inherent ability to resist corrosion. Often used in aerospace, pharmaceutical, and medical device industries, they meet ASTM, aerospace, and military passivation standards.

To perform a test, squeeze the dropper to apply the solution to the surface of a part. Keep the surface wet for six minutes before rinsing and drying it off. Do not scrub the solution off. If iron is detected, the surface will appear copper in color. If no copper coloring appears, the surface is clear of contaminants and is properly passivated. These bottles include enough solution to perform hundreds of spot tests.

This test is often used on all 200 and 300 series stainless steels and some 400 series stainless steel alloys. However, it’s not recommended to use this solution on 400 series stainless steel with less than 16% chromium. These stainless steel alloys will typically cause a false failure of the test.