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 gummite or shot Crete 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 BASK. 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."
Find swimming pool terms and their meanings here: