Water used to wash ordinary non-impure dirt from objects does not become musta‘mal merely because it touched and flowed off them.
If the material washed is actually impure, separate rules about transfer of impurity may apply. That issue must not be confused with the technical category of used water.
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Used Water: Definition, Ruling and Juristic Differences
Water used to wash ordinary non-impure dirt from objects does not become musta‘mal merely because it touched and flowed off them.
If the material washed is actually impure, separate rules about transfer of impurity may apply. That issue must not be confused with the technical category of used water.