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Hard water

Scale on the kettle, film on shower doors, soap that will not lather. Very common — and usually not a safety issue.

Scale is usually an aesthetic and appliance issue. It is not the same thing as a safety finding.

What people notice

White scale, spots on glassware, soap that will not lather. Hardness is minerals (mostly calcium and magnesium) — visible and annoying, easy to mistake for “contamination.”

What records usually show

Day-to-day cards may show a hardness number when lab samples exist. We label soft, hard, or very hard from that number (soft ≤60, hard about 60–180, very hard above ~180 mg/L as CaCO₃) and keep the mg/L on the card. Ontario has no health MAC for hardness — it is comfort and appliances, not a safety score. Hardness rarely drives the “worth a closer look” status.

What you can do

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