10 Levels of Salt Spray Test Standard

Level 10: No defect area, appearance rating A, no change in the surface appearance of the test specimen.

Level 9: Defect area accounts for ≤0.1%, appearance rating B, slight to moderate discoloration on the test specimen surface.

Level 8: Defect area ranges from 0.1% to 0.25%, appearance rating C, severe discoloration or extremely slight corrosion products on the test specimen surface.

Level 7: Defect area ranges from 0.25% to 0.5%, appearance rating D, severe loss of luster or extremely slight corrosion products appearing on the test specimen surface.

Level 6: Defect area ranges from 0.5% to 1.0%, appearance rating E, severe loss of luster, or thin layers of corrosion products/pitting distributed over local areas of the test specimen surface.

Level 5: Defect area ranges from 1.0% to 2.5%, appearance rating F, corrosion products/pitting present on the test specimen surface, with either or both distributed across the entire surface.

Level 4: Defect area ranges from 2.5% to 5%, appearance rating G, thick layers of corrosion products or pitting on the test specimen surface.

Level 3: Defect area ranges from 5% to 10%, appearance rating H, very thick layers of corrosion products or pitting, with deep pitting observed.

Level 2: Defect area ranges from 10% to 25%, appearance rating I, signs of base metal corrosion on the test specimen.

Level 1: Defect area ranges from 25% to 50%, indicating severe corrosion.