PROBLEM TO BE SOLVED: To prevent a chemical solution from flowing back to a tap water side by reliably carrying out switching between a supply circuit of the chemical solution to be used when sterilizing a fluid circuit in a medical unit using the chemical solution, and a tap water supply circuit to be used when treatment is performed.SOLUTION: A fluid circuit switching device 12 includes steps of: temporarily separating a water supply source 2 and a fluid supply source in a fluid tank 11 side in a non-contact state and connecting either one of the fluid circuit to the fluid circuits in the medical unit after going through the step of the separation.COPYRIGHT: (C)2012,JPO&INPIT【課題】医療用ユニット内の流体回路を薬液を用いて消毒する場合に使用する薬液の供給回路と治療の際に使用する水道水供給回路の切り替えを確実に行って薬液が水道水側に逆流しないようにする。【解決手段】水供給源2と流体タンク11側の流体供給源の回路を一旦非接触状態に分離する行程と、前記分離する行程を経た後に前記いずれか一方の流体回路を医療用ユニット内の流体回路に接続する行程とからなる流体回路切替手段12を備える。【選択図】図1
