On February 1, 2007, the hardness ranges were adapted to European standards and the millimoles total hardness per liter was replaced by the (from a chemical point of view, nonsensical) millimoles of calcium carbonate per liter.
Water supply companies will probably continue to publish the total hardness, but this is not required by law.
The new hardness ranges hardly differ from the previous ones, only ranges 3 and 4 are combined to form the hardness range "hard" and the numbers 1,2,3, 4, XNUMX and XNUMX are replaced by the already common descriptions "soft", "medium" and "hard". The new hardness ranges are defined as follows:
Table | Water hardness and conversions:
hardness range
soft (1)
Medium (2)
Hard (3 and 4)
Millimoles of calcium carbonate per L
less than 1,5
1,5 – 2,5
More than 2,5
hardness range
Less than 8,4°dH
8,4 to 14 °dH
More than 14 °dH
