Refrigerator Water Filter Cartridges for American style Fridges

NSF International is The Public Health and Safety Company™, providing public health and safety risk management solutions to companies, governments and consumers around the world.
Since 1944, NSF International, an independent, not-for-profit organization, has been committed to making the world a safer place for consumers. For more than 60 years, NSF has been the trusted third-party testing organization for product manufacturers that deliver and treat drinking water.
NSF Standards are recognised by the American National Standards Institute (ANSI) and the equivalent organisation in the European Community, the Dutch Council for Certification (RvC). NSF has also received the distinction of being appointed a Registrar for the International Standards Organization (ISO) and a World Health Organisation (WHO) Collaborating Centre for Water Safety and Treatment.

The NSF Mark is your assurance that the product has been tested and certified, and that the product meets requirements of strict public health standards. The NSF Mark conveys that an independent, third-party organization (NSF) has determined that the product complies with the relevant Standard. The end result for you: assurance that the system will do what it says it will do.

For a system to become NSF certified, it must meet the following requirements:

• Contaminant reduction claims are true;
• The system does not add anything harmful to the water;
• The system is structurally sound;
• Advertising, literature and labelling are not misleading;
• The materials and production processes don't change, giving you consistent product quality over time.

After NSF certifies or lists the product, NSF authorises the manufacturer of the product to use the NSF Mark on or in connection with the sale, use or distribution of that product.

These two standards are identical in their requirements for everything except contaminant reduction claims.

NSF/ANSI Standard 42:

• Is for aesthetic claims on microbiologically safe water only;
• Covers point-of-use (POU) and point-of-entry (POE) systems designed to reduce specific aesthetic or non-health-related contaminants (chlorine, taste and odour, and particulates) that may be present in public or private drinking water;
• The most common technology addressed by Standard 42 is carbon filtration;
• Chlorine reduction is broken down into classes that represent a certain level of Chlorine removal:
  Class I - 75% or greater Chlorine reduction
  Class II - 50% - 74% Chlorine reduction
  Class III - 25% - 49% Chlorine reduction
• Particulate removal means the system removes particles of a certain size based on the following classes:
  Class I - Reduces 85% of particles 0.5 to < 1 microns in size
  Class II - Reduces 85% of particles 1 to < 5 microns in size
  Class III - Reduces 85% of particles 5 to < 15 microns in size
  Class IV - Reduces 85% of particles 15 to < 30 microns in size
  Class V - Reduces 85% of particles 30 to < 50 microns in size
  Class VI - Reduces 85% of particles equal to or greater than 50 microns in size.

NSF/ANSI Standard 53:

• Is for health claims on microbiologically safe water only;
• Addresses point-of-use (POU) and point-of-entry (POE) systems designed to reduce specific health-related contaminants, such as lead, cyst, VOCs, turbidity, pesticides and herbicides, trihalomethanes (THM's) etc., that may be present in public or private drinking water;
• The most common technology addressed by Standard 53 is carbon filtration;
• Some products fall under the scope of both Standards 42 and 53 because they claim a combination of aesthetic and health claims;
• Lead reduction demonstrates the system's ability to reduce the concentration of lead below the U.S. EPA Maximum Contaminant Level;
• Cysts reduction indicates the system reduces the concentration of parasitic cysts by at least 99.95%. The cysts included in this claim are Cryptosporidium, Giardia, Toxoplasma and Entamoeba;
• V.O.C. reduction means the system reduces the concentration of all of the following contaminants: Alachlor; Atrazine; Benzene; Carbofuran; Chlorobenzene; 2,4-D; o-dichlorobenzene; p-dichlorobenzene; Lindane ect. Some of these chemicals can be tested individually for performance claims;
• Turbidity reduction means the system removes fine particulate matter that makes water appear cloudy to a level below the U.S. EPA Maximum Contaminant Level.

Most claims under both Standards 42 and 53 can be divided into two categories:

• Chemical Reduction: includes chlorine, VOC (Volatile Organic Chemicals), pesticides, herbicides and metals
• Mechanical Reduction: includes cyst, turbidity, asbestos and particulate

Activated carbon is carbon which has an electro-positive charge added to it and is highly porous. Activated carbon filters used for home water treatment typically contain either granular activated carbon (GAC) or powdered block carbon. Although both are effective, carbon block filters generally have a higher contaminant removal ratio.

There are two principal mechanisms by which activated carbon remove contaminants from water: adsorption and catalytic reduction.
Adsorption: involves the accumulation of molecules on the surface of a material, in this case activated carbon (organic compounds).
Catalytic reduction: involves the attraction of negatively-charged contaminant ions to the positively-charged activated carbon (residual disinfectants such as chlorine).

The two most important factors affecting the efficiency of activated carbon filtration are the amount of carbon in the unit and the amount of time the contaminant spends in contact with it. Particle size also affects removal rates. Activated carbon filters are usually rated by the size of the particles they are able to remove, measured in microns, and generally range from 50 microns (least effective) down to 0.5 microns (most effective).

Activated carbon filters remove/reduce many volatile organic chemicals (VOC), pesticides and herbicides, as well as benzene, chlorine (including cancer-causing by-product trihalomethanes), radon, solvents and hundreds of other man-made chemicals found in tap water. Some activated carbon filters are moderately effective at removing some, but not all, heavy metals. In addition, densely compacted carbon block filters mechanically remove particles down to 0.5 micron, including Giardia and Cryptosporidium, turbidity and particulates. Carbon block filters are generally better than GAC filters at removing sediment.

Over time activated carbon becomes filled with debris and no more contaminants can be adsorbed. Therefore, it is important to change the water filter every six months (unless otherwise stated) to ensure proper filtration at all times. Not changing the filter may allow contaminants and bacteria penetrate into your drinking water.

Water filter cartridges generally reduce contaminants in one of two ways.
First, water filters remove some contaminants mechanically, meaning that contaminants that are physically large enough are trapped in the pores of the filter. Other contaminants adhere to the surface of the filter media. Eventually, the surface area of the filter media becomes filled and no more contaminants can be adsorbed.
Or, the pores of the filter become so clogged with debris that water is unable to move through the filter effectively.
While it is easy to spot the decrease in the flow rate, it's not as easy to tell when the surface area of the filter media has become full and needs to be changed. Not changing the filter may allow contaminants penetrate into your drinking water.

Every water filter cartridge has an established "service live" from its manufacturer. The service life may be for a specific number of litres and/or an estimate of the number of months that a cartridge will last from its installation. In order to ensure optimal filtration to reduce contaminants, the filter should be changed when the end of the service cycle is reached (recommended by NSF International).

• is an organic chemical
• is a herbicide used to control broad-leaf weeds in crops like wheat and corn
• Potential Health Effects: kidney, liver, or adrenal gland problems
• Source of Contaminants in Drinking Water: runoff from herbicide used on row crops

• is an organic chemical
• is a herbicide used to control broad-leaf weeds in crops like wheat and corn
• Potential Health Effects: can cause damage to liver, kidney, spleen, lining of nose and eyelids; cancer
• Source of Contaminants in Drinking Water: runoff from herbicide used on row crops

• is an inorganic chemical
• is a notoriously poisonous metalloid with many allotropic forms, including a yellow (molecular non-metallic) and several black and grey forms (metalloids)
• Potential Health Effects: skin damage or problems with circulatory systems, and may have increased risk of getting cancer
• Source of Contaminants in Drinking Water: erosion of natural deposits; runoff from orchards, runoff from glass & electronics production wastes

• is an inorganic chemical
• is a naturally occurring silicate mineral with long, thin fibrous crystals found in a variety of building materials
• Potential Health Effects: increased risk of developing benign intestinal polyps
• Source of Contaminants in Drinking Water: decay of asbestos cement in water mains; erosion of natural deposits

• is an organic chemical
• is used as a herbicide to control broadleaf and grassy weeds
• Potential Health Effects: cardiovascular system or reproductive problems
• Source of Contaminants in Drinking Water: runoff from herbicide used on row crops

• is an organic chemical
• is one of the most toxic carbamate pesticides to control insects in a wide variety of field crops
• Potential Health Effects: problems with blood, nervous system, or reproductive system
• Source of Contaminants in Drinking Water: leaching of soil fumigant used on rice and alfalfa

• is an organic chemical
• is a colorless, aromatic liquid that is widely used in producing rubber, plastics, and other synthetic materials
• Potential Health Effects: anemia; decrease in blood platelets; increased risk of cancer
• Source of Contaminants in Drinking Water: discharge from factories; leaching from gas storage tanks and landfills

• is a disinfectant
• is a yellowish, poisonous gas with a pungent odour, widely used as a disinfectant in drinking water
• Potential Health Effects: eye/nose irritation; stomach discomfort
• Source of Contaminants in Drinking Water: water additive used to control microbes

• is an organic chemical
• is a colorless, flammable liquid widely used as an intermediate in manufacture of chemicals and insecticides
• Potential Health Effects: liver or kidney problems
• Source of Contaminants in Drinking Water: discharge from chemical and agricultural chemical factories

• are microorganisms (Giardia lamblia, Cryptosporidium)
• are chlorine-resistant microorganisms
• Potential Health Effects: gastrointestinal illness, accompanied by vomiting, diarrhea, and cramps
• Source of Contaminants in Drinking Water: human and animal fecal waste

• is an organic chemical
• is a colorless organic compound with a pleasant, aromatic odour used in the manufacture of pesticides, disinfectant and deodourants
• Potential Health Effects: liver, kidney or spleen damage; changes in blood
• Source of Contaminants in Drinking Water: discharge from industrial chemical factories

• is an inorganic chemical
• is a metal used in building construction
• Potential Health Effects:
  Infants and children: delays in physical or mental development; children could show slight deficits in attention span and learning abilities
  Adults: kidney problems; high blood pressure
• Source of Contaminants in Drinking Water: corrosion of household plumbing systems; erosion of natural deposits

• is an organic chemical
• is an organochlorine chemical that has been used both as an agricultural insecticide and as a pharmaceutical treatment for infestations of lice and scabies
• Potential Health Effects: liver or kidney problems
• Source of Contaminants in Drinking Water: runoff/leaching from insecticide used on cattle, lumber, gardens

• is an inorganic chemical
• is a heavy, silvery d-block metal that is used in thermometers, barometers, manometers, sphygmomanometers, float valves, and other scientific apparatus
• Potential Health Effects: kidney damage
• Source of Contaminants in Drinking Water: erosion of natural deposits; discharge from refineries and factories; runoff from landfills and croplands

• refers to particles of rust, dirt, sand, and sediment
• can either be in a solid or dissolved state
• Potential Health Effects: do not cause any adverse health effects, but they can sometimes carry other harmful organic, inorganic, and microbiological contaminants
• water that contains Particulates is typically cloudy, and as you might expect, tastes and smells "dirty".
• each filter's ability to remove particulates is measured against a certain "particulate class", or particle size. Class I - 0.5 to 1 micron, Class II - 1 to 5 microns, Class III - 5 to 15 microns

• is nothing more than dirt in drinking water
• doesn't cause any adverse health effects, but like particulates, sediment can carry other harmful organic, inorganic, and microbiological contaminants

There are four sources of tastes and odours in water distribution systems:

• 1.Compounds of biological origin - Tastes and odours of biological origin can be linked to an increase in the number of microorganisms at certain points in the system.
• 2.Disinfectant residuals and oxidation by-products - Tastes and odours caused by disinfectant residual can be from the residual itself or the reaction on the organic compound.
• 3.Emissions from pipes and storage facilities - In high concentrations, metals such as lead, copper, zinc and iron can cause tastes on the water as a result of corrosion of the plumbing system.
• 4.Diffusion of pollutants through synthetic pipes - Some pollutants such as hydrocarbons and phenols may diffuse through plastic piping so care should be given to which way pipes are laid.

• is an organic chemical
• was used as an insecticide
• Potential Health Effects: kidney, liver, or thyroid problems; increased risk of cancer
• Source of Contaminants in Drinking Water: runoff/leaching from insecticide used on cotton and cattle

• is the lack of clarity or brilliance in a water & interferes with water treatment processes
• is used to indicate water quality and filtration effectiveness (e.g., whether disease-causing organisms are present)
• higher turbidity levels are often associated with higher levels of disease-causing microorganisms such as viruses, parasites and some bacteria
• Potential Health Effects: microorganisms can cause symptoms such as nausea, cramps, diarrhea, and associated headaches
• Source of Contaminants in Drinking Water: soil runoff