Glossary

acidity - a characteristic that can make water corrosive and unpleasant; acidity must generally be corrected with neutralization

activated carbon - carbon which has been chemically treated to improve its adsorption properties and filtration capacity

adsorption - the process by which contaminants react with activated carbon and are removed from water

aeration - an oxidation process in which air is injected into water generally to convert an unwanted substance into a solid form that can be filtered

brine - the solution a water softener uses to clean its media bed of captured calcium and magnesium in preparation for service

brine drum - the brine preparation and holding tank on a water softener

calcite - the media used in a neutralization system to neutralize acidic water

carbon filtration - a common water filtration method which uses activated carbon to adsorb contaminants

chlorine - a common water disinfectant used by municipal water utilities

conditioned water - water free of dissolved calcium and magnesium (hardness minerals); also referred to as soft water

countercurrent regeneration - a type of regeneration in which the flow through a water conditioner is reversed during the cleaning process for greater effectiveness and efficiency

cryptosporidium - probably the most common and certainly the most notorious of a group of microorganisms called cysts; "crypto" was responsible for a major waterborne illness outbreak in Milwaukee in 1993

cysts - any of a group of microorganisms that include entamoeba, giardia and cryptosporidium; when ingested, cysts can cause gastrointestinal illness among others and often have more problematic effects on children, the elderly and people with immune deficiencies

demand-initiated regeneration (DIR) - a process in which regeneration is initiated based upon a household’s water use instead of at a preset interval

drinking water - the one percent of a household’s entire water use that is designated for drinking or food preparation; also referred to as food grade water

ferric iron - dissolved iron which has been oxidized and transformed into an orange particulate

ferrous iron - dissolved iron; often found in well water

hard water - water that contains dissolved calcium and magnesium

hardness - the amount of dissolved calcium and magnesium in a water sample, typically measured in grains per gallon (gpg)

hydrogen sulfide - an obnoxious gas with a "rotten egg" odor found in some water

ion exchange - a water softening process in which hardness ions (calcium and magnesium) are exchanged for sodium or potassium ions

iron - a common element that is absorbed by water as it passes through the ground; iron is often found in well water and can cause rusty orange stains on clothing and household fixtures

lead - a tasteless, odorless water contaminant that may be leached from lead-based solder used to join pipes

manganese - iron’s close cousin commonly found in well water; manganese can cause black stains on clothing and household fixtures

neutralization - the process by which water’s acidity is adjusted to a neutral range; acidic water can be corrosive

oxidation - a process in which an oxidizer (commonly air or chlorine) reacts with a dissolved substance to convert it into a solid form that can be filtered

recovery rate - a measure of a reverse osmosis system’s efficiency; generally measured as amount of water produced divided by amount of water used; a rate of 25% is usually considered efficient

regeneration - a water conditioner’s cleaning cycle; the cycle prepares the system’s resin bed so it can soften water again

resin - tiny beads used by a water conditioner to soften water; the place where ion exchange occurs inside a water conditioner

reverse osmosis - a filtration method in which water is forced through a semipermeable membrane which rejects contaminants

scale - a hard, crusty substance that remains after hard water dries

soap scum - the substance which results from the reaction of the hardness minerals in water with common household soaps; usually evident as a bathtub ring or glass shower door film

soft water - water free of dissolved calcium and magnesium (hardness minerals); also referred to as conditioned water

solder - a substance used to join pipes; lead-based solder was outlawed in the late 1980s

source water - untreated water that is supplied to a home or business; source water is usually best for outdoor applications like watering lawns

turbidity - water cloudiness caused by suspended particles

volatile organic compounds - organic contaminants including commercial chemicals and pesticides; commonly referred to as VOCs