What system is primarily used for water laboratory test calculations and results?

The metric system is primarily used for water laboratory test calculations and results due to its universal acceptance and standardization in scientific contexts. This system is based on powers of ten, which allows for easy calculations, conversions, and understanding of measurements. For instance, in water chemistry, concentrations of contaminants or chemicals are often expressed in milligrams per liter (mg/L) or micrograms per liter (µg/L), which are metric units.

Using the metric system simplifies communication and data sharing across different laboratories and regulatory bodies internationally, ensuring consistency in reporting and analysis. It allows for precise measurements, which are critical in ensuring safe drinking water standards. Moreover, many scientific protocols and regulatory standards are established using metric measurements, further solidifying its usage in the field of water treatment and analysis.