Activated Carbon: Water treatment media used in various forms, powdered, granular or block. Carbon can originate from various sources such as coal, wood or coconut shell. When heated to 700-800 degrees C. in the absence of oxygen, it forms a carbonized char and this process “activates” the carbon. This char can then be grounded to its’ needed size and is very efficient at de-chlorinating water and removing tastes and odor from water and air.

Chlorine: A yellow-greenish gas that is added to water to protect the consumer from bacteria and other microorganisms. It is widely used because it is inexpensive, easily injected into water, and due to its’ concentration, a gallon can treat a large amount of water; however, chlorine use does have its’ drawbacks. When chlorine is used as a disinfectant it combines with naturally occurring decaying organic matter to form THM’s.

Chloramines: A chemical formed by mixing chlorine and ammonia used to disinfect many municipal water supplies. Chloramines do not combine with organics to form carcinogenic THM’s. Water containing chloramines should not be used for fish or kidney dialysis. Chloramines are more difficult to remove from water than chlorine and carbon filters should be sized properly to provide necessary contact time for chloramines removal.

Cyst: A protective shell produced by the host (Cryptosporidium, Giardia, etc.) during the reproductive cycle. The cyst is 3-10 microns in size and is impervious to chlorine and UV. Ultra-filtration will remove cysts from the water.

E. coli: One of the members of the coliform bacteria family found in human and animal intestines. These bacteria are indicative of fecal contamination in the water. Introduction of an antioxidant (chlorine, UV, ozone) are needed to kill the bacteria. Ultra-filtration removes E. coli not killed by the chlorine.

Ferric Iron: A small iron particle which is suspended in water and gives water its’ “rusty water” appearance. Iron in this state is easily removed by ultra-filtration.

Ferrous Iron: Iron that is dissolved in water and is also called “clear water” iron. This type of iron will be removed when oxidized by chlorine that changes the iron into a particulate. Once in particulate form, this iron will be removed by ultra-filtration.

Hardness: A term used to determine the waters’ content of calcium and magnesium. The higher the level of calcium and magnesium makes the formation of soap bubbles more difficult. High levels of hardness make the water difficult to work with, hence the term “hard water”. This is corrected by installing a water softener. .1 grain of hardness = 17.12 ppm (parts per million) of TDS. See water softening.

Heavy Metals: Metallic elements with high atomic weight such as mercury, chromium, cadmium, arsenic and lead. They can damage living organisms at low concentrations and tend to accumulate in the food chain. RO is necessary to remove metals from the water.

Nitrites/Nitrates: Ammonia in fertilizers is converted or broken down from ammonia to nitrites to nitrates. Nitrites are toxic, but because they are an intermediary stage between ammonia and nitrates, they don’t normally occur in high concentrations under normal conditions. Ammonia as a fertilizer is water-soluble which over time percolates into underground wells where it is converted from nitrites to nitrates. Nitrates in levels over 5-10 ppm (parts per million) bond with the hemoglobin in blood and take up space not allowing oxygen to bond to the hemoglobin starving the body of oxygen. This isn’t necessarily dangerous to adults but can be threatening to infants under one year old. The infant will actually begin to turn blue due to lack of oxygen thereby coining the term “blue baby syndrome” or cyanosis. RO is necessary for the removal of nitrites or nitrates.

NSF: An independent not-for-profit third party testing organization that verifies manufacturers’ product and their performance claims to maintain public health and safety.

Organics: A term used to describe any or all compounds, natural or man-made with chemical structure based on carbon. Examples are petroleum-based products such as plastics, solvents, pesticides and herbicides.

Oxidize: The addition of an oxidant (oxygen, ozone, chlorine, peroxide) to water that forces the contaminant (iron, sulfur, hydrogen sulfide) from a dissolved state to a precipitated particulate form that can be removed by ultra-filtration.

Particulate: A very small solid suspended in water, which can vary widely in size, shape, density and electrical charge.

Reverse Osmosis: A water treatment process where water pressure is used to push water through a semi-permeable membrane that removes most of the minerals. During this process, water constantly flows across the membrane and is flushed to the drain so the membrane does not become plugged with the removed minerals. Depending on the RO system design, the RO can send anywhere from 3-7 gallons of water to the drain to make 1 gallon of RO water.

Tannins: The result of decomposing organic matter (leaves and decaying vegetation) in water. Tannins impart a faint yellowish to brown color to water. Tannins are found predominately in areas where the water table is very near the surface of the ground. A good example of tannins is dropping a tea bag into a cup of hot water and noting the color change. Due to various types of the original organic matter, some tannins may be removed by ultra-filtration while in other cases, chlorination combined with activated carbon may be necessary to remove them.

THM: THM’s are a by-product that is created when chlorine is combined with organic material during the water disinfection process. Chloroform is one of these by-products and is a suspected carcinogen, In order to prevent THM formulation, municipalities have switched from chlorine to chloramines. Long contact time with deep bed GAC (granular activated carbon) is needed to reduce/remove THM’s from water.

TDS: Total dissolved solids is the total weight of the solids that are dissolved in water measured in ppm.

Turbidity: The amount of small particles in solid matter suspended in water or a measurement of the amount of dirt in the water. Turbidity is measured in Nephelometric Turbidity Units (NTU) and on potable water supplies, should not exceed 0.30 NTU’s. The MCL set for turbidity set by the EPA is 1.0 NTU.

Virus: A parasitic infectious microbe that can cause disease in humans, Viruses can reproduce only in living cells and most are larger than .025 microns in size.

VOC’s: Volatile Organic Chemicals are a type of chemical that can be both man-made and naturally occurring in water. Water from well and utilities may contain some of these contaminants. Some VOC’s are pesticides, herbicides or insecticides that seep into the ground water after application. Other VOC’s enter the water supply through industrial or other waste disposal. This category also includes

THM’s that are a by-product of the disinfection process. Water containing VOC’s should not be consumed after boiling as this causes the VOC’s to concentrate in the water. Removal of VOC’s is accomplished by deep bed GAC (granulated activated carbon) and requires certain contact times to be absorbed by the carbon.

Water Softening: The process of exchanging calcium and magnesium ions (hardness) for sodium or potassium ions through the use of an ion exchange media. This process takes place in a pressurized tank that has a bed or resin beads that are “loaded” with sodium or potassium ions. As the hard water passes through the resin bed the calcium and magnesium adhere to the resin bead displacing the sodium or potassium ion into the water. The resin has a limited capacity for hardness and must be regenerated periodically with a brine solution and can be regenerated for years.