Water hardness is one of the most popular analyses when it comes to water quality determination. Each bottle of mineral or sparkling water provides information about its calcium and magnesium content. Calcium is essential for the human body, especially for the skeletal system, and is required to be consumed in high amounts. The highest uptake of Ca for humans is via milk and other dairy products. In second place comes mineral water, which also contains high levels of magnesium, indispensable for life.

However, calcium and magnesium naturally present in water are the primary cause of tubes and pipes clogging which can lead to failures and loss of efficiency for several kinds of processes. Due to these reasons, water hardness (calcium and magnesium) must be determined frequently to ensure that a sufficient amount of nutrients are contained while avoiding frequent pipeline issues and shutdown of any affected processes or utilities.

Generally, this is performed manually with visual indication (e.g., ASTM D1126, ASTM D511, EPA 130.2, EPA 215.5, APHA 130.2, and APHA 2000), an unreliable method with less reproducible results, prone to human error. A new norm (ASTM D8192) solves these issues and allows the measurement of water hardness objectively without the disadvantages of using visual endpoint determination.