Guide
Hard water hair
Hard water carries a lot of dissolved calcium and magnesium. Hair samples exposed to very hard water every other day for three months came out weaker, and the standard for Chiang Mai’s city water does not allow water that hard. A building’s own well is not covered by that standard, so ask your landlord or building office whether your water comes from the city or a well.
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What does hard water do to hair?
Hair samples exposed to hard water held more minerals afterwards than samples exposed to purified water. Samples exposed to less hard water every other day for a month stayed as strong as samples in purified water.
What hardness limit does Chiang Mai’s city water have?
The standard for Chiang Mai’s city water caps hardness at 300 mg/L. Hardness is stated in milligrams per litre (mg/L): the higher the number, the harder the water.
Which supply is yours?
If your building is on the city supply, that limit applies to your water. If it has its own well, ask whether the water has been tested for hardness, and compare the result with that limit.
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