Choosing Water Filters

KINDS OF WATER BASED ON USAGE

In general, water usage can be classified into Utility Water, Washing/Bathing Water, Drinking/Cooking Water, and Commercial/Industrial Water.

1.    Utility Water – Home and community water for plants, garden, lawn, yard and driveway cleaning, toilet flushing, fire fighting, irrigation, road and street cleaning, etc. It may not be of the highest quality and may not even be free from microorganism. It should perhaps only be color free and odor free.

2.    Washing/Bathing Water – Water for these purposes, i.e., bathing, shampooing, personal grooming, laundering and dishwashing, need to be “soft” or free from Calcium and Magnesium salts to minimize soap and detergent usage, and minimize occurrence of scales on the surface when dried. Presence of “hardness” (or Calcium and Magnesium salts) makes it difficult to produce suds when using soap to wash. Car washing can also be included in this category because of the need for the car finish to be free from scales or mineral deposits when dried.

3.    Drinking/Cooking Water – Water to be used for drinking and cooking must be of the highest quality. It must be relatively free from harmful contaminants like microorganisms, viruses, organic chemicals, heavy metals, pesticides, disinfectants, odor, taste, and coloration. Since it is not possible to produce pure H2O (except probably in the laboratory) that is completely free of these contaminants, the allowable levels are established by standards set by location-specific regulating government agencies, i.e., EPA of the USA, etc.

4.    Commercial/Industrial/Institutional Water – In general, the quality of water required by this user classification range from high quality to extremely high quality. For example, commercial establishments like laundries, beauty salons and car washers will need soft water that is free from color, odor, and micro-organisms. Industries need the water for rinsing, steam power generation, chemical processes, unit operations, etc. In these cases, the water requirements need to be high quality and should be free from hardness, chemicals, metals, colors, odors, micro-organisms, and are de-ionized. In specialized institutions like hospitals and laboratories, the requirement is for an extremely high quality water, specific to the application at the point of use.

The type of water filters to use depends on the type of contaminants that have to be eliminated. To identify the contaminants, a sample of the raw water supply is sent to a water testing laboratory for analysis. The result of the laboratory analysis will then become the basis of determining the specific filter or the combination of water filters to use. In some instances, some other purification processes may need to be included to make the overall filtration effective and economical.