Tap Water & Pure Water
When we turn on the tap and run a glass of water, it’s easy to look at it and think of it as pure water. However, strictly speaking that’s not the case. Just to be clear, we are not saying tap water is unsafe (that is a different thing) but it does contain both natural minerals etc alongside chemicals which are added for cleanliness etc – most commonly heard of would be chlorine and fluoride.
So let’s talk about it the context of tests we do rather than testing drinking water which is a very different thing. We will leave that to the specialists and water companies!
What is Pure Water?
Pure water is a generic term often used to describe water that has been purified (effectively water that is free of impurities) which nowadays most commonly refers to mechanical filtration to remove particles in water. However, it can refer to different types which are not the same thing.
A few examples of things people sometimes refer to as ‘pure’ – Filtered Water, De-ionised Water and Distilled Water. All of which are different things.
Pure Water Uses
There are many different uses for pure water, especially in scientific and industrial applications. For example, we mentioned in a separate article about how when we do Salts Analysis Tests we use purified water so that it does not impact on the test we do do find out what the water source is, typically for water damage restoration or water leak detection.
Why is that important? – well say we are testing a damp area of plaster to understand if it is a water leak or rising damp causes, we are looking to see if chlorides are present (to determine it is a tap water leak) or nitrates from ground water sources, or to see if neither are present. So when we do the test, using tap water would clearly show chlorides, that is why we use purified water in salts tests.
Another common day-to-day use of purifiedwat water that you may have heard of is…
Pure Water Window Cleaning
In what is normally referred to as ‘Traditional Window Cleaning’, window cleaners generally use soapy water which they use to clean windows and then squeegee it off to remove water residue. In the more modern version of window cleaning, commonly using ‘Water Fed Poles’, people use purified water.
Why do Window Cleaners use Pure Water?
Window cleaners use pure water, put simply, to achieve better results with their window cleaning. Because it is difficult for them to squeegee the water off at height (because they work from the ground), they let the water dry naturally, letting the water evaporate. With pure water, no residue is left behind leaving only clean windows.
Its a bit like when you clean your car using tap water from a hose pipe. If you let it dry naturally, the impurities are left behind leaving spots or streaks on your car, these are especially noticeable on your car windows.
Window cleaners usually get their water from one of three methods:
- Reverse Osmosis (RO) water systems
- Deionisation (DI) water systems
- Purchased purified water – from suppliers who sell purified water
Reverse Osmosis (RO) vs Deionisation (DI)
Each of the above has advantages and disadvantages – Deionisation (DI) is generally quicker and cheaper to produce water but generally requires ‘resin’ which needs replacing from time to time (otherwise it does not purify the water as well). In comparison, Reverse Osmosis (RO) systems are more expensive and slower to produce water, however, proponents of it consider that it delivers better more reliable results (if done right) and is often considered more environmentally friendly.
How do you Measure Water Purity?
There are many different methods of measuring water purity, however, perhaps he most common and simple method of measuring water purity is by measuring Parts Per Million (PPM) of Total Disolved Solids (TDS), with those solids being anything that is not the water (H20) particles themselves. This is often measured using a TDS Meter, which gives a quick reading. They are relatively inexpensive.
The higher the TDS reading, the lower the water purity in general. However, please remember it is only carrying out a simple test, you do not want to be using a cheap TDS meter to decide on the quality of water, for example for drinking. That is more sophisticated. Plus, remember that some things found in water (certain minerals for example) are not necessarily harmful, clearly other things could be (even in very small quantities).
We are only talking about use of a TDS in tests we do, e.g. Salts Tests.
What is a TDS Meter?
A TDS (Total Dissolvable Solids) Meter is a device which measures the number of impurities in water and usually measures them in Parts Per Million (PPM), showing the results on the meter. By way of example, we ran a test of the tap water in our area and it showed 118 PPM.
We then repeated the test using the purified water we use and, it showed zero parts per million, making it very pure indeed, which is what you would wish for for tests such as salts tests that we use for identifying the source of water leaks.
If you have had a water leak, or think you might have one, but cannot find it. Get in touch with our team today and we will be glad to help you guide the process of one of our leak detection engineers coming to your property (domestic or commercial leak detection) to help find and fix your water leak.