Definition - What does Corrosion Index mean?
Corrosion index is a measure of water quality that is used to determine whether the water will cause corrosion in the pipes or will form a scale that can create blockages.
The Langelier Saturation Index (LSI) is the most widely used corrosion index. A LSI value of zero indicates a balanced water, which is ideal.
Trenchlesspedia explains Corrosion Index
The Langelier Saturation Index (LSI) takes into account the pH, conductivity, total dissolved solids, alkalinity and total hardness of the water. The index is a calculation of the difference between the actual pH and the theoretical pH of the water based on its chemistry. An index value of -5 indicates that the water has a high corrosivity and should be treated. An index value of zero indicates balanced water. An index value of +5 indicates that the water has a high tendency to form scale and should be treated.