How do I remove hard water spots from car windows?
Fresh mineral spots on glass often respond to a glass-safe acidic water-spot remover used on cool glass and then rinsed thoroughly. Older, heavier deposits may need a glass polish. Glass is harder than paint, but it can still be etched by long-term mineral deposits; etched glass may require professional glass polishing. Keep acidic products off paint, trim and rubber seals, and dry windows after washing to prevent recurrence.
References
- Hardness of Water, U.S. Geological Survey
- The Physical and Chemical Properties of Water, Drinking Water Inspectorate (UK)
- Hard water, Wikipedia
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