Lab Standards for Distilled Water Systems

Water quality ranks as essential for maintaining scientific and medical laboratory standards. Factors such as pH -- the measure of acidity and alkalinity in water -- and bacteria and mineral deposits can contaminate samples.

The Facts

• Generating and using distilled water proves costly. Three grades indicate lab water quality, ranging from 1, as the highest, to 3. Each grade serves for a specific set of tasks. For safety and accuracy, lab workers must know when to use the highest-grade water. For economic reasons, they must determine when a lower grade will suffice.

Types

• Type 3 water works for cleaning beakers and other glassware, filling machines and reservoirs, and in systems that don't require higher-grade water. Buffers, culture media such as agarose gel and reagent solutions used in experiments and other common laboratory processes can employ Type 2. Critical lab techniques and processes, including DNA sequencing or polymerase chain reaction, where micro-sized particles quantify the results of an experiment, require Type 1.

Significance

• Maintaining water quality in the laboratory is critical. As a preventative measure, some laboratories substitute Type 1 water for Type 2. Any analytical process involving water as an ingredient or substrate requires the highest grade to prevent foreign microbes from ruining results.