N-Q

Neutralizer - A chemical used to make chlorine or bromine harmless. Used in test kits to counteract the bleaching effect of the chlorine or bromine in order to increase the accuracy of pool water tests. Sold as chlorine and bromine neutralizer, it is used to destroy excessive amounts of chlorine or bromine, so the high levels will not affect swimmers.

Nitrogen - A gas that causes algae to bloom and disables chlorine. It is brought into the water each time it rains. Maintaining proper chlorine levels will prevent nitrogen from becoming a problem. Super chlorination will remove nitrogen and its related compounds.

Non-Chlorine Shock - A term given to a class of chemical compounds that are used to oxidize or shock the water (destroy ammonia, nitrogen and swimmer waste). They contain no chlorine or bromine and do not kill living organisms. Swimmers may re-enter the water in only 15 minutes after adding a non-chlorine shock.

Noryl - The brand name for a thermoplastic resin used in the manufacture of certain pump components and various other pool equipment fittings.

O

Organic - Refers to volatile, combustible and sometimes biodegradable chemical compounds containing carbon atoms bonded together with other elements. The principal groups of organic substances found in water are proteins, carbohydrates, fats and oils. See organic waste.

Organic Waste - Also called swimmer or bather waste - All of the soap, deodorant, suntan lotion, lipstick, makeup, cologne, body oils, sweat, spit, urine, etc., brought into the water. They also form chloramines, which are foul-smelling and body irritants. Requires large amounts of chlorine or non-chlorine shock to destroy.

ORP - An abbreviation for oxidation reduction potential. It is a measurement of a body of water's ability to oxidize contaminants. Measured with an electrode and an electronic meter. It is an indication of the sanitizing level or degree of safety from disease in the water. Measured in millivolts with the accepted minimum level being 650 mV (millivolt).

OTO - Abbreviation for orthotolidine. A chemical reagent used to test the total chlorine level in pool and spa water. It does not measure free available chlorine. See DPD.

Over-Acid - An incorrect term used to describe water that is acidic or water that has a pH lower than 7.2.

Overdrain - Also called a diffuser or distributor - An internal sand filter device that evenly distributes influent pool water over the sand filter bed.

Oxidation - To rid the water of ammonia, nitrogen compounds and swimmer waste (organic compounds). These organic compounds disable chlorine, are body irritants and have a foul smell. Removal is accomplished by superchlorination or by shock treating with a non-chlorine oxidizer.

Oxidizer - A non-chlorine shocking compound that removes or destroys built-up contaminants and chloramines in pool water without raining chlorine levels as required when "super chlorinating."

Ozonator - A gaseous molecule comprised of 3 atoms of oxygen. It is generated on site from air or oxygen and used for oxidation of water contaminants.

P

Pathogenic Organism - An organism that causes disease.

Petcock - A small, manually-operated faucet or valve for draining off liquids or releasing air pressure. The air-relief valve on a filter is an example.

pH A term used to indicate the level of acidity or alkalinity of pool water. Too low of pH causes etched plaster, metal corrosion and eye irritation. Too high of pH causes scale formation, poor chlorine efficiency and eye irritation. The ideal range for pH in swimming pools is 7.4 to 7.6.

Phenol Red - A chemical reagent dye used to test for pH. It can measure pH from 6.8 to 8.4.

Plaster - A mixture of white cement and white marble dust used as an interior finish, which can be tinted, colored or left white; applied to the gunite or shotcrete of a pool or spa.

Polymer - A substance made of giant molecules formed by the union of simpler molecules. Many water clarifiers are made from organic polymers. An example would be polymerized ethylene, called polyethylene.

Potassium Peroxymon - Potassium Peroxymonosulfate - The active ingredient and chemical name of a non- chlorine shock treatment or non-chlorine oxidizer. Does not kill bacteria or algae but it will oxidize or destroy ammonia, nitrogen and swimmer waste. It has a low pH, and it does not increase chlorine or bromine levels the way that super chlorination does, so water may be entered in 15 minutes after addition. It will also reactivate bromine to its killing form, hypobromous acid.

PPM - An abbreviation for parts per million. It is a weight-to-weight expression. It means 1 part in 1 million parts, such as 1 lb. of chlorine in 1 million lbs. of water. Many of the common pool water tests, as well as acceptable ranges, are stated as ppm. For example, free available chlorine should be kept between 1.0 and 3.0 ppm; total alkalinity should be between 80 and 120 ppm; and and water hardness should be between 200 and 400 ppm.

Precipitate - A substance separating, in solid particles, from a liquid as a result of a chemical or physical change. It also means to form a precipitate.

Precoat - Depositing diatomaceous earth (D.E.) onto the filter grids or elements.

Pressure Gauge - A gauge with an analog dial indicating the pounds per square inch (psi) of pressure that has built up within a closed container, such as a filter.

PSI - An abbreviation for pounds per square inch.

Pump - A mechanical device, usually powered by an electric motor, which causes hydraulic flow and pressure for the purpose of filtration, heating and circulation of pool and spa water. Typical, a centrifugal pump is used for pools, spas and hot tubs.

Pump Capacity - The volume of liquid a pump is capable of moving during a specified period of time. This is usually gallons per minute (gpm).

Pump Curve - Also called a pump performance curve - A graph that represents a pump's water flow capacity at any given resistance.

Pump Strainer Basket - A device placed on the suction side of the pump, which contains a removable strainer basket designed to trap debris in the water flow without causing much flow restriction. Sometimes called a "hair-and-lint trap".

Q

QUATS - Quaternary Ammonium Compounds - Also called Quats - The chemical compounds of ammonia used as algaecides and algaestats.

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