Water for injection (WFI)

Highly purified water used to prepare parenteral products and for final rinses of product-contact equipment, with limits for conductivity, total organic carbon, microbial count and endotoxin. It is produced and distributed in a dedicated system, typically kept hot and recirculating, that is qualified and monitored. The Japanese Pharmacopoeia has its own monograph, and pharmacopoeias have differed over which production methods are allowed, with membrane-based methods broadly accepted only in recent years. Check which pharmacopoeia a supplier's WFI claim refers to.