RO water is often used for general laboratory tasks such as rinsing, washing or feeding laboratory instruments such as dishwashers, autoclaves and ASTM Type 1 (ultrapure) water purification systems. ASTM Type 2 (pure) water purification systems often use an integrated reverse osmosis step as pretreatment. RO water quality depends on the feed water and differs depending on the modules, region and season. Therefore, it should not be used when water of a consistent quality is called for.