From a biological standpoint, lab water has many distinct properties that are critical for the proliferation of life. This transparent fluid is the major constituent of the fluids of living things. As a chemical compound, a water molecule contains 1 oxygen and 2 hydrogen atoms that are connected by covalent bonds. Lab water has many uses in our world, from drinking, washing, transportation, recreation, food processing, to industrial applications, chemical uses, and as a scientific standard.
We often take water quality for granted in daily life and our work, and we also might not be aware of the different grades of water, the appropriate water grade applications or the cost to obtain the desired grade. Laboratories need reagent grade water (RGW) for experiments and animal water in order to reduce the risk of scientific variability, or to prevent bacterial disease.
Common Water Contaminants and How to Measure Them
Water is known as the universal solvent because more substances dissolve in it to varying degrees than in any other solvent. Depending on what the water will be used for, it requires a certain purity. Water quality is dependent on the combination of water treatment systems and technologies employed to effectively remove contaminants to levels required for critical applications. Thus, purified water is mechanically filtered or processed in order to remove impurities and make it suitable for use. The impurities that may need to be removed are:
- endotoxins and nucleases
- inorganic ions
- organic compounds
Tap water contains many substances that, if left untreated, may react or catalyze reactions in undesired ways. It is important to know: the conductivity of the water, the organic content of the water and the presence or absence of endotoxins. These are the most important things to know, as far as laboratory water is concerned. Conductivity is the tendency of water that contains ions to conduct electricity, and is measured in Siemen(S), microsiemens/centimeter or microohms/cm. This measurement is used to measure feed water and lower quantities of treated water.
In order to obtain pure water for a laboratory, it takes and incredibly sophisticated lab to test it to the level that lab technicians want for their water.
What Does Lab Water Grade Mean and Why Does It Matter?
Reagent grade water (RGW) is water that is suitable for use in a specified procedure, as it does not interfere with the accuracy, precision and specificity of the procedure. Water specifications have been described by ASTM (American Society for Testing and Materials) D1193, ASTM D5196, ISO (International Organization for Standardization) 3696 and CLSI® (Clinical and Laboratory Standards Institute (formerly NCCLS) C3-A4.
There are national specifications for a variety of different grades of water and depending on what the laboratory is doing, whether it is a clinical application, an industrial application, or manufacturing, they know which one of those grades of water they need. Typically, people say they want an “X” amount of water per day or per 8-hour shift and give a grade number: I, II, III or IV.
Different levels of quality are required for a vast range of applications, therefore different grades of water must be purified and utilized to match the required procedures or appliances.
At Dime Water Inc., we are not able to test to the levels that lab technicians want, but we can provide laboratories with custom-built water treatment systems to remove all impurities from the water. If the lab is on a municipal water supply, we can get enough information from that and the treatment processes are such that, regardless of what the water supply is, we can take care of it by knowing more about their water we can do a better job of sizing the equipment for a certain type of contaminant. A package-approach to treating lab water is going to have ultraviolet, mixed bed DI, reverse osmosis, recirculation, and there will be some ozone production on top of it all, for knocking down the organics.
Often, labs select the highest possible grade of water when it really is not necessary, and they are spending money on equipment and on maintenance that far exceeds what they really need. However, they can be just as safe and more in line economically if they used a grade of water that was more compatible to what their process is. If you build a water system for a certain grade of water but later on you need it for a higher grade, it can always be upgraded to a higher level. 2 or 3 components have to be replaced based on water volume and/or time.
After treatment, water should not be stored statically. Water of this grade is circulated through the treatment processes, so there is constantly a circulation taking place.
At Dime Water Inc., our engineers are always prepared to help you choose the right water treatment technology to meet your needs. Contact us at 760.734.5787!