Description | Quantity |
Scale forming but non corrosive | >2 |
Slightly Scale forming and Corrosive | 0.5 - 2 |
Balanced but pitting corrosive possible | 0.02 - 0.5 |
Slightly corrosive but non scale forming | −0.5 - 0.02 |
Serious corrosion | −0.5 to −2 |