The Science of Laundry
Credits: The following information is adapted from info complied by Shirley, the resident laundry expert at Bummis.
Water
Water is 99+% of what we wash with, therefore the quality of your water is critical for the best washing results. If you have even medium-hard water you should seriously consider investing in a water softening device. Costs are quickly recovered by savings on detergent and by reducing wear and tear on appliances, fabric and plumbing.
Water hardness is a measure of the calcium and magnesium carbonate present in your water. Other factors in water that can affect washing include total dissolved solids, chlorine, iron (yellowing), alkalinity (problems rinsing, harsh fabric), organic matter, etc. So, in other words, water quality is crucial to washing success.
The Other 4 Main Factors of Washing Success
The other main factors in washing success are chemical action (detergent), mechanical action (swooshing), water temperature, and time (how long the wash cycle lasts). These four components need to fill the pie chart.

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