Inputs
Result
Effective treatments
Ion exchange softener (whole house) · Reverse osmosis (at the tap) · Nanofiltration
Commonly assumed to work, but does not
Activated carbon · Sediment filters · UV · Magnetic and electronic descalers, for which the evidence is weak
Before you buy
Check the specific product is certified for this specific contaminant
A technology being capable is not the same as a product being certified.

Method

Maps the selected contaminant or problem to treatment technologies known to be effective against it, and to those commonly assumed to work but which do not.

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