|
| Information on related products can be found on the following pages:
|
| Whole House Carbon Filter Systems |
Water Filters and GAC
Granular
Activated Carbon (GAC) water filters remove volatile organic chemicals
(VOC), pesticides and
herbicides, trihalomethane compounds, radon, solvents and hundreds of
other man-made chemicals found in tap water.
Chemicals Removed by Activated Carbon
Drinking water containing
high levels of volatile organic compounds (VOCs) may be harmful to human
health. VOCs are a class of chemicals that have important properties
in common: They evaporate or vaporize readily (they are volatile), and
they contain carbon (and are therefore called organic). When present in
water at low concentrations, some VOCs produce a sweet, pleasant odor.
The U.S. Environmental Protection
Agency (EPA) estimates that VOCs are present in one-fifth of the nation's
water supplies. They can enter ground water from a variety of sources.
Benzene, for example, may enter ground water from gasoline or oil spills
on the ground surface or from leaking underground fuel tanks. Other
examples of commonly detected VOCs are dichloromethane (methylene
chloride), an industrial solvent; trichloroethylene, used in septic system
cleaners; and tetrachloroethylene (perchloroethylene), used in the
dry-cleaning industry.
Volatile organic compounds may
have a variety of harmful health effects. At high levels of exposure, many
VOCs can cause central nervous system depression (drowsiness, stupor). All
can be irritating upon contact with the skin, or to the mucous membranes
if inhaled.
Drinking water containing one or more VOCs at levels
above standards should not be consumed. VOCs may also enter the body
through skin absorption or through inhalation of water vapor. In
addition, because little is known about the additive effects of these
chemicals, special attention should be paid to detecting and eliminating
VOC sources if two or more chemicals are found in water. In any case,
sources of VOC contamination should be eliminated if possible.
Home Water Filter Options
Filters can be installed for
point-of-use (P.O.U.) treatment at the faucet or point-of-entry (P.O.E.)
treatment where water enters the home. P.O.E. or Whole House Water Filter Systems are
recommended for VOC removal to ensure that all water used for drinking,
cooking, cleaning, and bathing is free of contamination.
Granular activated carbon (GAC) filters are typically
used to reduce VOC levels in home drinking water. The effectiveness of
carbon filters is related to (1) the type and amount of contaminant, (2)
the rate of water usage, and (3) the type of carbon being used. Large
contaminant concentrations and high water use rates reduce the carbon
life. Manufacturer's guidelines for replacing carbon filters should be
followed. Water entering and leaving the filter should be tested
periodically to ensure that the treatment system is working properly.
Bacteria may grow on the surface
of a carbon filter. It is recommended that water be disinfected after it
passes through the filter to ensure its safety. Many types of disinfection
systems are available. Ultraviolet
(UV) light disinfection is one type of system shown to work effectively
and efficiently to eliminate bacteria problems in water.

|