WHAT IS IT?
Water hardness refers to the concentration of mineral compounds in a given quantity of water, particularly magnesium and calcium salts. Water commonly referred to as "hard" has a high concentration of these salts, while "soft" water contains very little.
The most commonly used unit of measurement for hardness is the French hydrometric degree (º HF), and the calculation of this parameter follows the following formula:
(mg/l Ca x 2.5 + mg/l Mg x 4.2) /10
HOW IS WATER HARDNESS GENERATED?
The presence of magnesium and calcium salts in water depends primarily on the geological formations the water passes through before being collected. Groundwater that flows through carbonate aquifers (limestone) is the hardest, and these aquifers are composed of calcium and magnesium carbonates.
Groundwater from aquifers with a predominantly silicate composition (e.g., granites) results in soft water, that is, with very low amounts of calcium and magnesium salts.
HOW DOES WATER HARDNESS AFFECT OUR DAILY LIVES?
A very noticeable effect of water with different hardness levels (hard water and soft water) is its different behavior when soap is added. With the same amount of soap, much less lather is produced in hard water because the calcium and magnesium react with the soap compounds, rendering them ineffective. This necessitates adding more soap in hard water.
The most well-known effect in places where the water supply has a high hardness is the formation of calcareous scaling (commonly referred to as limescale).
It's important to know the water hardness in your area, as this information allows you to adjust the operation of certain appliances that offer this option (especially washing machines and dishwashers). This pre-adjustment of the appliance will allow it to change its operation based on the selected value, thus compensating for the negative effects that hard water can cause, resulting in better performance and a longer lifespan for the appliance.
Water hardness classification (° HF):
– < 7: very soft water – 7-14: soft water – 14-32: medium hardness water – 32-54: hard water – > 54: very hard water
List of hardness levels in municipalities according to FACSA
IS WATER HARDNESS REGULATED BY LEGISLATION RELATING TO WATER FOR HUMAN CONSUMPTION?
No limit has been established for this parameter since the World Health Organization determines that whether the water hardness is high or low, there is no harmful effect on people's health.
