Which type of water is used during autoclave processes?

• A. Tap water
• B. Filtered water
• C. Distilled water
• D. Mineral water

Answer: (C)

Water quality is critical in autoclave processes because the steam used for sterilization must be pure to avoid introducing minerals or contaminants that can leave deposits, reduce heat transfer, or cause corrosion in the equipment and on sterile packs. Distilled water is produced specifically to remove minerals, salts, and impurities, giving mineral-free steam. This helps prevent scale buildup inside the boiler and steam lines, maintains consistent sterilization conditions, and protects the autoclave and its contents.

Tap water often contains minerals, chlorine, and potential microbes, which can form deposits, corrode components, and affect steam quality. Mineral water has minerals by design, which can leave residues and interfere with sterilization performance. Filtered water may remove some particulates, but it may not eliminate dissolved minerals to the level required for reliable autoclave operation. Therefore, distilled water is the best choice to ensure clean, efficient, and safe sterilization.