Water Filter Glossary

water filter terms explainedStruggling to understand the description of a water filter?

Don't despair, you are not alone. The terminology to describe water filters, how they work and perform is not common knowledge.

But here is a list of terms to help you understand the lingo better.

Adsorption is a chemical process that takes place in carbon based water filters. The filter media attracts certain water contaminants so they no longer bond with water molecules. Instead they attach themselves to the filter media.
Chemical Filtration
Chemical filtration is process, that takes place i.e. in water softeners. The filter media holds an atomic charge that attracts certain water contaminants. While the filter media is charged, the pull is strong enough to separate these contaminants from the water molecules.
Multimedia filter
Multimedia filters consist of two or more chambers with different kinds of filter media. One of them usually is carbon based filter media.
Particulates are the particles of sand, sediment, rust and dirt present in drinking water. Particulates often make the water look cloudy. Sometimes it also effects the smell and taste.

There are no known adverse health effects from particulates alone. But they are much bigger than most other, unhealthy contaminates. So if you find particulates in your water, chances are high, that there are also other, harmful contaminants in this water.

To find out more about your water filter's ability to remove particulates, look at the "particulate class" or particle size it filters out.

It is measured in micron and classified by size:
Class I - 0.5 to 1 micron
Class II - 1 to 5 microns
Class III - 5 to 15 microns

One micron equals approximately 1/25,000 inch or one millionth of a meter.

Some filter manufacturers use the term "nominal particulate" instead of telling you the exact particulate class. In other words, they tell you that their filter removes very small particulates.

A measure of the general acidity or alkalinity of a liquid, measured on a scale of 0 - 14. 7.0 is neutral. Everything from 0 to 6.9 is considered acidic, while the range from 7.1 to 14 is called basic.

The pH level of water has an influence on the effectiveness of filter media.

Physical Filtration
Physical filtration is a process where contaminants that a bigger than water molecules are blocked from passing through.
Potable is another term for drinkable water in terms of water quality.
Slow sand filter
Slow sand filters block contaminants that are bigger than sand crystals. As most water contaminants are much smaller, this type of filter is not very effective against chemical water pollutants.
THMs or Trihalomethanes
THMs are byproduct when water that contains natural organics is chlorinated. THMs are linked to various types of cancer.
VOCs or Volatile Organic Chemicals
VOCs are a group of synthetic chemicals dissolved in water. They vaporize at low temperatures, hence the name. Most insecticides and herbicides belong to this group.