Glossary of Terms





Absolute:  a term to describe a 99.99% retention of particles greater than the specified micron rating.

Absorption: the process of one substance actually penetrating into the structure of another substance.

Acidity:  the quantitative capacity of water to neutralize an alkali or base.

Acid Rain:  atmospheric precipitation through adsorption of carbon dioxide, nitrogen and sulfur oxides in the air with a pH below 5.6.

Activated Carbon:  a medium made from heating a carbon based substance such as coconut shells or coal in a controlled atmosphere such as steam.  The process forms a highly porous structure with an electrochemically active and adsorptive surface. Activated carbon is commonly used in water treatment to remove objectionable taste and odors and for the reduction of chemical contaminants. 

Adsorption: the physical process occurring when liquids, gases, or suspended matter adhere to the surfaces of, or in the pores of, an adsorbent medium.  Adsorption is a physical process which occurs without chemical reaction.

Aeration:  the process whereby water is brought into intimate contact with air by spaying or cascading, or air is brought into intimate contact with water by an air aspirator or by bubbling compressed air through the body of water.  Both pressure (closed) aerators and open (gravity) aerators are used.  Closed aeration is used chiefly for oxidation:  open aeration for degassing.

Aerobic:  an action of process conducted in the presence of air, such as aerobic digestion of organic matter by bacteria.

Algae:  single-celled or simple multi-celled organisms, commonly found in surface water, which produce their own food through photosynthesis.  Excess algae growth may cause the water to have undesirable odors or tastes, and decay of algae can deplete the oxygen in the water.

Algal Bloom: an unusual or excessive abundance of algae growth.

Alkalinity: the quantitative capacity of water to neutralize an acid, the measure of how much acid can be added to a liquid without causing a significant change in pH. 

Ambient Temperature:  the outside air temperature of the temperature of a given piece of equipment that is operated on a continuous basis.

Amoeba:  a single celled protozoan that is widely found in fresh and salt water.  Some types of amoebas cause diseases such as amoebic dysentery. 

Anaerobic:  a condition in which in which there is no air or no available free oxygen.

Anaerobic Organism:  an organism that can thrive in the absence of oxygen (air), such as bacteria in a septic tank.

Anion:  a negatively charged ion in an aqueous solution.

Aqueous:  containing water; watery.

Aquifer:  a natural underground formation where groundwater is stored.

Aragonite: a form of calcium carbonate that appears in pearls. 

ASTM Grade Water: very high purity water produced to meet the standards outlined the American Society for Testing and Materials

Axial Flow:  (Longitudinal Flow) a flow pattern in which water travels from the bottom to top (or vice versa) in either a cartridge-type or loose media tank-type filtration system. The advantages are greater contact time, higher unit capacity, more complete utilization of medium and more uniform water quality.

Back Pressure:  pressure which creates resistance against a flow of water.

Backflow:  the flow of water in a pipe or line in a direction opposite to the normal flow.  Backflow is a problem if there is back siphonage or back pressure causing reverse flow from a cross connection.

Backflow Preventer:  a device or system installed in a water line to stop backflow from a non-potable source.  

Bacteria:  single celled organisms which lack well-defined nuclear membranes and other specialized functional cell parts and reproduce by cell division or spores. Bacteria may be free living organisms or parasites. Bacteria along with fungi are decomposers that break down the wastes and bodies of dead organisms, making their components available for reuse. Bacterial cells range from about 1-10 micron in length and from 0.2 to 1 micron in width.   They exist almost everywhere on earth. Some bacteria are harmful to humans most are helpful.

Bactericide:  any substance or agent which kills bacteria. 

Bacteriostatic:  having the ability to inhibit the growth of bacteria without destroying the bacteria. 

Baffle:  a deflecting barrier to affect the flow pattern 

Ballast:  the power supply to activate and regulate voltage in an ultraviolet (UV) lamp.

Bar:  a unit of pressure.  One bar equals 14.5 pounds per square inch (psi), or about 0.987 standard atmosphere.

Beaver Fever:  see Giardia lamblia.

Biocide:  a chemical which can kill or inhibit the growth of living organisms such as bacteria, fungi, molds and slimes.  Biocide can be harmful to humans as well.

Biodegradable:  subject to degradation (break down) into simpler substances by biological action.  Example: the breakdown of detergents, sewage, wastes, and other organic matter by bacteria.

Bleach: a strong oxidizing agent and disinfectant formulated to break down organic matter and destroy biological organisms. 

Blinding:  the reduction or shutting off of flow due to filter medium or membrane fouling.

BOD: biochemical oxygen demand. 

Bored Well:  A shallow  (10-100 feet) large diameter well (8-36 inches) constructed by hand-operated or power driver augers.

Brackish Water:  water containing dissolved solids in the range >1000 to

Brine (reject water):  a strong solution of salt(s) with total dissolved solids concentrations in the range from 40,000 - 300,000 or more milligrams per liter.

CA:  cellulose acetate.

Calcite:  1. Calcite carbonate (CaCO3) 2. a trade-name for finely ground grades of marble or limestone, very high in calcium carbonate which are used to raise the pH reading of low pH water.

Carbon (C):  an element which is found in almost all living or formerly living matter including plants, proteins, organics, and hydrocarbons. 

Carcinogens:  a substance that can cause cancer. 

Cartridge:  any re-moveable pre-formed or pre-packaged component containing a filtering medium, ion exchanger, membrane, or other treatment material which fits inside a housing to make up a cartridge filter.  Also referred to as an element.

Cation:  an ion carrying one or more positive charges.

Caustic:  any substance capable of burning or destroying animal flesh or tissue.  The term is usually applied to strong bases.

Cellulose Triacetate (CTA):  a cellulose ester obtained by introducing the acetyl radical of acetic acid into cellulose to produce a tough plastic material which is used to make the cellulose type of semipermeable reverse osmosis membrane. 

Centigrade: a temperature scale in which 100 degrees is the boiling point and zero degrees the freezing point for water a sea level. Also know as Celsius.

Centimeter (cm):  one one-hundredth  (1/100) of s meter (m).

CFU:  colony forming units.

Channeling:  the flow of water or regenerate through a limited number of passages in a filter or ion exchanger bed, as opposed to the usual distributed flow through all passages in the bed. 

Charcoal:  an absorbent carbon product which has a bout one-third the surface area of activated carbon. 

Check Valve:  a valve which allows water to pass in one direction but will close and prevent flow (backflow) in the opposite direction.      

Challenge Water: water specifically prepared for testing the performance of water treatment equipment products. 

Chloramines:  chemical complexes formed from the reaction between ammonia and chlorine being used to disinfect many municipal water supplies.

Chlorine:  a gas widely used in the disinfection of water and as an oxidizing agent for organic matter, manganese, iron and hydrogen sulfide.

Chlorine Demand:  a measure of the amount of chlorine which will be consumed by organic matter and other oxidizable substances in a water before a chlorine residual will be found.  The difference between the total chlorine fed and the chlorine residual.

Clear water Iron:  see ferrous iron.

COD:   chemical oxygen demand.

Coliform Bacteria:  A particular group of bacteria primarily found in human and animal intestines and wastes. These bacteria are widely used as indicator organisms to show the presence of such wastes in water and the possible presence of pathogenic (disease-producing) bacteria.

Colloidal Matter:  see colloids

Colloids:  very fine solid particles, typically between 0.1 and 0.001 microns in diameter, which are suspended in liquid or gas and will not settle out of a solution and cannot be removed by conventional filtration alone.  When in sufficient concentrations, colloidal matter may give  grayish cast to a standing water sample.

Colony-Forming Units (cfu):  see heterotrophic plate count.

Color:  a shade or tint which imparted to water by substances which are in true solution and thus cannot be removed by mechanical filtration.  color is most commonly caused by dissolved organic matter, but it may be produced by dissolved mineral matter.

Combined Available Chlorine:  the total chlorine, present as chloramine or other, derivatives, which is present in a water and still available for disinfection and for oxidation of organic matter.  The combined chlorine compounds are more stable than free chlorine forms, but are somewhat slower in action

Cyst:  a capsule or protective sac produced about themselves by many protozoans, as well as some bacteria and algae as preparation for entering a resting or a specialized reproductive stage. Similar to spores, cysts tend to be more resistant to destruction by disinfection. Fortunately, protozoan cysts are typically 2 to 50 microns in diameter and can be removed from water by fine physical filtration.

Deionized:  product of treatment by a cat ion and anion exchange system.

Density:  the mass of a substance per specified unit of volume. Example: pounds per cubic foot. True density is the mass per unit volume excluding pores, apparent density is the mass per unit volume including pores.

Distillate:  product of treatment by a distiller

Filtrate:  product of treatment by a filter unit

Gland Nut (UV): nut used to seal one end of the ultraviolet (UV) reactor chamber.

GPD:  gallons per day.

GPM:  gallons per minute.

Gravity Flowa flow that occurs under the natural pressure due to gravity.

Gravity Powered:  a flow that is created by the natural pressure of gravity.

Hydrologic Cycle:  the complete circuit pursued by water in nature, including (1) falling of precipitation such as rain, hail, sleet, snow, dew (2) the journey of fallen water over and through the earth’s surface formations and (3) eventual evaporation of the water and its return to the atmosphere to again fall as precipitation.

Intensity (UV lamp):  lamp intensity is defined as the overall power of the lamp and is most often designated in watts. Also called power density, intensity refers to total lamp output across the entire electromagnetic spectrum.

LB:  Luminor Blackcomb UV system

LBH:  Luminor Blackcomb high output UV system

Mega Joules:  mW/cm2 x seconds = mj/cm2. To better understand this concept it is important to distinguish between basic lamp intensity and intensity or amount of light at the working surface. The quantity of light at the working surface is defined in either intensity units or energy units. Light intensity at the product surface, described by the term irradiance, is a measure of momentary exposure and is most often quantified in milliwatts/cm2. Light energy at the surface is a measure of cumulative intensity exposure (intensity x time), quantified as millijoules/cms, and is simply mW/cm2 x seconds =mj/cm2

Microbiological:  a branch of biology dealing with microscopic forms of life (microbiology).

Microorganism:  a living organism invisible or barely visible to the naked eye and generally observable only through a microscope. They may also be called a microbe. Microorganisms are generally considered to include algae, bacteria, fungi, protozoa and viruses.

Mold:  a superficial often woolly growth produced on damp or decaying organic matter or on living organisms. A fungus, as of the order of Mucorales, that produces mold.

Municipal Water:  water that has been processed at a central plant to make it potable or safe to drink, which is then distributed to homes and businesses via water mains. Water in most urban and suburban areas vs. water obtained from separate proprietary sources such as private wells or springs.

Nano: a combining form with the meaning "very small, minute," used in the formation of compound words (nanoplankton): in the names of units of measure it has specific sense "one billionth" (10 to the minus 9) nanomole; nanosecond.

Pathogen:  any disease producing microorganism.

Pathogenic:  capable of causing disease

Phage:   viruses infecting bacteria are termed bacteriophages. Those infecting fungi are termed mycophages.

Potable (drinking water) Water:  a water supply which meets U.S. EPA and or state water quality standards and that is considered safe and fit for human consumption.

Process Water:  water used in a manufacturing or treatment process or in the actual product manufactured. In many cases water is specifically treated to produce the quality of water needed for a specific process or application.

Product Water:  water that has been through the treatment process and meets the quality standards required for the use to which the water will be put. Product water is called by different names, depending upon which treatment process it has gone through:

“Distillate” from distiller / “Filtrate” from filter unit / “Finished” from a municipal treatment plant / “Deionized” from a cation and anion exchange system / “Softened” from softener unit / “Permeate” from a reverse osmosis or ultra-filtration unit.

Permeate:   product of treatment by a reverse osmosis or ultra-filtration unit - devices with ultrafine porous substance or membrane.

Protozoa:   microscopic, usually single-celled microorganisms which live in water and are relatively larger in comparison to other microbes. Protozoa are higher on the food chain than the bacteria that they eat. Many protozoa are parasitic. Singular form: protozoan or protozoon.

Pure Water:   this term has no real meaning unless the word “pure” is defined by some standard such as AAMI grade water, CAP grade water or pharmaceutical grade water.

QR Codes:  a QR code (quick response code) is a matrix barcode first designed for the automotive industry. It is used to store links to a specific page on the Luminor web site.   The pages include service videos (i.e. how to change a UV lamp or quartz sleeve)

Quartz Sleeve:  is a component of the Ultra Violet (UV) system, it is the thermal barrier between the UV lamp and the water.

Raw Water:  water usually from wells or surface sources, which has had no previous treatment and is entering a water processing system or device. Raw water is also defined as water at the inlet side of any Watertreatment system or device.

Recycled Water:  water that has been used once for one purpose and is then re-processed or treated by a water or wastewater treatment system and that processed (product) water is used for a secondary purpose. For example:   the use of wastewater effluent for irrigating golf courses and parklands

Spore:  a single celled or several celled reproductive body that detaches from the parent and gives rise, directly or indirectly to a new individual: a general term. Spores are usually microscopic, of many different types, produced in various ways. Spores occur in all plant groups, in fungi, bacteria and protozoan.

Softened:  the product of treatment by a water softener unit.

Sweet Water:  A non-technical expression meaning fresh water vs. salt water.

Tap Water:  typically, water drawn from a faucet (at the tap) and considered safe to drink. It may be delivered, potable/municipal/city water quality or private well water considered “fit to drink”

TOC:  total organic carbon, or the amount of carbon covalently bound in organic compounds in a water sample. TOC is measured by the amount of carbon dioxide produced when a water sample is atomized in a combustion chamber.

Ultrafiltration (ultra-filtration): filtration using a medium fine enough to retain colloidal particles, viruses, or large molecules.

Ultra Violet:  those rays beyond the visible spectrum at its violet end. Radiation having a wavelength shorter than wavelengths of visible light and longer than X-rays. Radiation in the region of the electromagnetic spectrum includes wavelength from 100 to 3,900 angstroms.

UV Sensor:  in relationship to an Ultra Violet (UV) system, it is an optical instrument that incorporates a photodiode that reads the UV light inside the UV systems reactor chamber.

UVT:  ultra violet transmittance, is the percentage of the UV light's ability to penetrate through the water.

Validation:  as defined in the water treatment industry, determination upon testing that a representative sample of a water treatment equipment model has met the requirements of a specific standard.

Virus:  one of a group of minute infectious agents (20-300nm long and/or wide), unable to multiply except inside a living cell of a host, of which they are obligate parasites and outside of which they are inert.

Water Treatment:  a general term including any processing step (physical, biological, or chemical means) used to purify, modify, improve, and enhance water to meet desired water quality needs or to meet set quality standards. Usually called Water Processing.

WB:  denotes the wide body structure of a water filter, generally 4.5” in diameter.

Well Water:  water that is draw from a well.

We are continually updating our Glossary of Terms. Please check back in the future to see what new information has become available.