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Technicalities and Abbreviations

When my quest first began in bringing this website to the internet, I was actually looking for a product that would improve the quality of the water in my own home. Just like you, this was something a little new to me and I quickly became pretty confused over all the industry jargon that’s used to describe what certain water filters or softeners do.

So I decided to add an informational page on all the possible water contaminants (which you can find here) and I also thought it would be a good idea to have a page which explains any abbreviations or technicalities you come across and haven’t got a clue what they mean.

So here it goes…

CTO – Chlorine, Taste, Odor
This one kind of speaks for itself, and is often found in water filters that use cartridges.

GAC – Granular Activated Carbons
This abbreviation will often be found when a manufacturer is describing a type of filter they have included in their product, the filter that is responsible for making sure both the taste and odor of your water is dealt with.
Granular activated carbons have thousands of “mini-pores” to adsorb water contaminants and improve the quality of water.

GPD – Gallons per Day
Again, this speaks for itself.

MCL – Maximum Contaminant Level
Something the EPA (see below under organizations) has put in place to protect your health when substances are added at source.

TDS – Total Dissolved Solids
This is the measurement of the number of total inorganic or organic compounds found in water. In other words anything that’s present other than H2O, (pure water). The higher the TDS measurement, the harder your water is going to be.

TFC – Thin Film Composite
You will normally come across this abbreviation when you’re looking at water filters which use reverse osmosis. A TFC is typically a semi-permeable membrane which is used during the filtration process.

THMs – Trihalomethanes
When chlorine reacts with certain other naturally occurring elements in water, these toxins are formed and can be a health issue.

RO – Reverse Osmosis
The water filtration techniques that uses TFC. More about this can be found on my page on reverse osmosis filtration.

Psi – Pounds per Square Inch
You will come across this abbreviation when talking about water pressure. The higher the number, the higher your water pressure will be.

VOC – Volatile Organic Compounds
These are a group of chemicals that all have various properties in common. They readily vaporize or evaporate (hence volatile), and contain carbon (hence organic).These compounds will only enter your water when they come from another source such as oil or chemical spills.


So, that’s some of the technical abbreviations you may come across, but I’m not done yet. There are various organizations involved with water filtration and softening, and I have noticed they are often abbreviated. So if you’ve come across one of these, rather than have you go and look for the answer elsewhere on the internet, I have included them below for you:
ANSI – American National Standards Institute
EPA – Environmental Protection Agency
NSF – National Sanity Foundation
WQA – Water Quality Association

The list above only includes the abbreviations I have come across during my research. If you can’t find the one you’re looking for, I would love to hear from you so it can be added here. In my humble opinion, the more people that can find all the information they need in one place, the better!

Please email your suggestions to info (at)
( anti-spam notation, please remove spaces and replace(at) with @ )

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