Langelier saturation index measurement context
A calculated index from the measured pH, total dissolved solids, alkalinity and calcium, and the water temperature. A positive index means the water tends to deposit calcium carbonate scale; a negative index means it tends to dissolve calcium carbonate. It indicates a tendency and is not a direct measurement of corrosion. Disinfection
Define where the property is measured
Specify field or laboratory measurement, units and the sample state needed for the project. A delivered sample may not preserve the source-time condition for a changing property.
Include the complete project requirement
Provide the matrix, target analytes, required method, fraction, units and reporting limits. Include the permit or monitoring instructions where results will support a regulatory submission. Naming this method does not establish blanket compliance eligibility.
Resolve collection before sampling
Use the bottle, preservation and delivery instructions assigned to the agreed scope. Identify each location and collection time, and document any deviation. The final analytical plan must fit the submitted material and its intended use.
Related testing & guidance
Technical & service references
Vanguard service detailsSource review: November 8, 2026. The agreed method and project scope govern the testing.