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How to Select the Right Water Purification System for Your Laboratory

Water is the most essential solvent for all laboratories. While the usual tap water may well be fairly pure, you still need to be wary of the five classes of contaminants that may wreak havoc on your daily lab routine—particulates or colloids, organics, bacteria, gases, and inorganic ions. All these may affect the water quality, which is critical for the success of your lab experiments.

To enhance the quality of water, you have to choose a water deionization system based on the level of purification you are trying to achieve. Common processes include distillation, activated carbon, ion exchange, microporous filters, reverse osmosis, ultrafiltration, ultraviolet radiation, and continuous deionization. However, each type of lab application may require different water purification systems.

Things to consider when choosing the right lab water purification system

To choose the right water deionization systems for your purifying needs, you must consider the factors below. Knowing these will help you choose the right water purification system.


Each water purification system is designed based on the feed water quality, as well as the nature of the application. Furthermore, a single lab may require different types of water for various applications such as:

  • Biochemistry
  • Biology
  • Biotechnology
  • Chemistry
  • Diagnostics
  • Pharmaceutics


Types of Water Quality Standards

The type of water quality used in your laboratory is crucial. Avoid common mishaps like sullied samples, errors in readings, and hours upon hours of wasted time and effort. By understanding water quality standards that are required for your lab, either ASTM, CLSI, CAP, or USP will assist us in the selection of the system to meet your needs. Yamato’s Auto Still WS201 and WS221 are specifically distilled water purification systems. Other Yamato Auto Still WG204, WG251, WG1001, WA511, WA711, and WA731 water purification systems can produce distilled water as well as deionized Type I water. This wide selection gives you different distilled water production rates from 1.5L/hour to 10L/hour.

Below is a quick overview of the types as defined by the American Society for Testing and Materials (ASTM).

Type I

Known as ultrapure water, this water has a resistivity of more than 18 megohm-cm. Usually, Type I water is required for analytical labs and includes applications such as high-pressure liquid chromatography, gas chromatography, cell or tissue culture, mass spectrometry, and any procedures dealing with trace elemental laboratory instrumentation.

Yamato’s Auto Pure WA300 Analytical, WB300 Biological, WC300 Analytical Low TOC, and WG300 Biological UV Sterilizer series can produce ASTM Type I water. Based on the requirement such as endotoxin, particulates, TOC, and Rnase/Dnase, you can choose a suitable unit from the selection.



Type II

Type II water quality has a resistivity of over 1 megohm-cm. While this is cleaner than Type III water quality, it is not ultrapure. Lab processes such as sample dilution, media preparation, radioimmunoassay, and electrochemistry require this type of water quality. Moreover, it is ideal

for use in feeding lab instruments and clinical analyzers because of its low calcium buildup. The Yamato Auto Still WG204, WG251, and WG1001 water purifiers can produce Type II quality distilled water. The Yamato Auto Pure WH201 and WH501 series can produce Type II quality deionized water.


Type III

With resistivity of more than 4 megohm-cm, Type III water is produced through Reverse Osmosis, which removes 90 to 99 percent of contaminants. Water purification systems such as the Yamato WH Auto Pure Water Purifier system WH201 and WH501 series use low-odor mixed bed cartridges for general deionization, humidification, battery water refilling and glassware washing and rinsing. These models are also ideal for hydrogen generators, sterilizers, environmental chambers, ultrasonic cleaners and chiller loops.



Type IV

Type IV water quality has a resistivity of 200 kiloohm-cm and is produced through reverse osmosis. Typically, this type of water is used as feedwater to either a Type I or Type II water deionizer system. The Yamato Auto Still WA511, WA711, WA731, WS201, and WS221 can produce Type IV quality distilled water.



Water Usage Requirements

Aside from the various types of water quality and its applications, you also have to take note of the total water volume requirements of your laboratory per day. Determining if water usage is in large batches or continuous flow is critical. Knowing peak demand for water is also important.

Feedwater Quality

Feedwater quality is an important factor to produce each type of quality water and most critical for providing type I water. Pretreatment is often required. Pretreatment options may include distillation, deionization, and reverse osmosis.

Monitoring and traceability

Make sure that the water purification system can meet specification requirements for your desired water grade. Look for features such as resistivity monitors to measure ionic purity and total organic carbon meters. By doing this, you will detect the amount of organic material in water. Also, look for water purification systems that enable ease in tracing and recording water quality in the laboratory.

Certification of the equipment and compliance

Inspect aspects concerning quality assurance. Look for products from ISO 900 and ISO 14001-registered manufacturers and documents such as a certificate from the maker certifying quality, calibration, and conformity. Also, make sure that the product complies with safety regulations and ask for CE, UL, and FCC-certification.

Your lab’s floor space

Take into consideration the available floor space in your lab. Are there space limitations? There are options for countertop, wall mounted, remote dispense and free standing water purification systems.

All Yamato Auto Pure models WA Analytical, WB Biological, WC Analytical Low TOC, and WG Biological UV Sterilizer Series are benchtop, with remote dispense option while the Auto Pure WA Series and WH201/501 can be wall mounted. The Labo Cube WL320A and WL320B are other space saving models as they can be installed under a fume hood or sink or on a table. They also have casters for easy mobility.

Auto Still WA511, WA711 and WA731 are free standing units that are ideal for large laboratories with enough room for a large capacity water purification system.

User-friendly interface

A good water purification system should also have a user-friendly interface to boot. Search for models with basic automated features such as remote access capabilities, system dashboards, enhanced data management control, and long-term electronic archiving. A touch screen interface like Yamato’s Auto Pure WA Analytical, WB Biological, WC Analytical Low TOC, and WG Biological UV Sterilizer Series would also be highly convenient.

Water quality monitors

Monitoring sensors are incredibly essential as these can guarantee with 100% accuracy the water quality and the total amount of contaminants. Most Yamato water purification system models are equipped with a water quality monitor. Also, make sure to look for products with leak detection and real-time quality monitoring which are standard features of WA Type 1 Ultrapure Analytical, WB Type 1 Ultrapure Biological, WC Type 1 Ultrapure Analytical Low TOC, and WG Type 1 Ultrapure Biological UV Sterilizer Auto Pure Water Purification Systems.

Eco-friendliness and Cost-effectiveness

Also, choose products that offer low ownership cost and low-cost consumable cartridges to save money. It is important that your consumables are filled with the highest quality media but at a reasonable cost. Moreover, water purification systems like the Pure Line WL100 from Yamato guarantee economical production of deionized water, easy maintenance, and zero need for AC power, making this perfect for

labs wishing to reduce their carbon footprint.

Customer support

Lastly, when buying water purification systems, choose products from brands that offer after-sales services—from a one-year warranty on the product and customer service/technical support. This will suggest reliability and integrity in the brand.

Choose the right lab water purification system. Trust Yamato Scientific.

For over 130 years, Yamato Scientific has been offering a long line of superior products and services from ovens and sterilizers to spray dryers, and ultra-pure water systems. To know more about our high-quality lab water purification systems, visit, call 1-800-292-6286, or contact our customer support through