Containers and Storage for Pure Water in Analytical Laboratories

Industry insiders know that, according to the national standard GB/T6682-1992, purified water for analytical laboratories is classified into three grades: Grade I, Grade II, and Grade III. All grades of water should be stored in sealed, dedicated polyethylene containers. Grade III water may also be stored in sealed, dedicated glass containers. New containers should be soaked in a 20% hydrochloric acid solution for 2-3 days before use, and then rinsed repeatedly with laboratory water several times.

During storage, the main sources of contamination for each grade of water are the dissolution of soluble components in the container, carbon dioxide from the air, and other impurities. Therefore, Grade I water should not be stored and must be prepared immediately before use. Grade II and Grade III water can be prepared in appropriate quantities and stored separately in corresponding containers that have been pre-washed with the same grade of water.