What is the method used to make hard water suitable for clinical purposes?

The method that is typically used to make hard water suitable for clinical purposes is ion exchange. This process effectively removes the calcium and magnesium ions that contribute to water hardness and replaces them with sodium or potassium ions. The result is 'softened' water that is more appropriate for various clinical applications, as it reduces the potential for mineral buildup in clinical equipment and improves the efficacy of detergents and cleaning agents.

In contrast, distillation does remove impurities by boiling water and then condensing the steam, but it is not specifically designed to address the hardness of water. It typically results in pure water but does not selectively remove hardness-causing minerals. Filtration may help to eliminate some particulates but is generally ineffective at altering the hardness of water. Boiling can help kill bacteria but does not change the concentration of minerals that cause water hardness. Thus, ion exchange remains the most effective choice for addressing the hardness of water in clinical settings.