Distillation is the most practical means of preparing consistently pure reagent grade water on a laboratory scale. This is the case because distillation is extraordinarily effective at removing all types of contaminants, requires no expendables, only light maintenance and is easily monitored. Deionization is a quick process that produces high purity water that is without scale buildup. Deionized water is ideal for use in situations in which particles within the water may produce undesirable results. Both systems provide a constant supply of pure water for most laboratory applications.