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Glossary of Terms

Activated Carbon
A granular material normally produced by heating wood or coconut shells in the absence of air. Used to remove taste, odours & many chemicals from water.
Removal of both in-organic & organic ionized minerals & salts from water by a two-phase ion exchange method.
Removal of in-organic ionized minerals & salts by process similar to deionation.
A process in which pathogens (bacteria) are killed by chlorination, UV light, boiling, etc.
Extended Pass Carbon Block. This filter is made from a porous carbon block and provides microfiltration (0.5 microns) for cyst removal as well as many chemicals.
A characteristic of natural water due to the presence of dissolved calcium & magnesium; hard water gives rise to scale formation & reacts with soap.
Basic metric unit of volume; one litre of water weighs 1000 grams.
A linear measure equal to one millionth of a meter.
An unstable form of oxygen (O3). It is a strong oxidizing agent and used as a water disinfectant.
Parts Per Million. Indicates the number of parts by weight of a dissolved or suspended contaminant per million parts by weight of water.
Permanent Hardness
Water hardness due to presence of chlorides and sulphates of calcium & magnesium which will not be precipitated by boiling.
Reverse Osmosis
A process that reverses by application of pressure the flow of water through a semi-permeable membrane, so that it passes from the more concentrated side to the more dilute side.
This term refers to a sediment removal cartridge filter for removal of suspended solids like sand, dirt, and rust.
Soft Water
Water, which contains less than 17.1 mg/L of hardness minerals.
A process in which all living organisms are destroyed.
A measure of finely divided suspended matter in water that causes the scattering and adsorption of the light rays, making the water look cloudy.
Ultraviolet Light
That band of the electromagnetic spectrum where disinfection takes place. Usually the 254nm band output given by the UV lamp.
UV Lamp
A low-pressure Mercury vapour lamp giving 254nm wavelength suitable for UV disinfection.

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