抄録
Recently there have been a lot of fetal accidents by Legionella disease originated in bathtubs. Some point out the importance of facility management of circulation filtration system, hot spring storage tank, bathtubs etc. to prevent the accidents, as well as water quality management. Chlorine is a disinfectant most generally used. The authors analyzed the water quality of various hot spring waters. ORP (Oxidation Reduction Potential) and free residual chlorine concentration at the time of chlorine addition were investigated, and the relation of water quality was examined.
