Optimal maintenance strategy On medical instruments used fOr haemOdialysis prOcessOptymalna strategia kOnserwacji urządzeń medycznych wykOrzystywanych w prOcesie hemOdializy Haemodialysis machines are one of the important medical equipment which is used to treat renal failures and minimum downtimes are thus essential. Uninterrupted and constant use of these machines in hospitals worldwide makes them vulnerable to failures if not maintained properly. Consequently, the maintenance cost for dialysis machine is high. A method to implement a cost effective maintenance strategy is demonstrated in this work. Root Cause Based Maintenance (RCBM) strategy is employed at the component level to optimize the Reliability Based Maintenance schedules derived from the existing maintenance and failure data. In order to minimize the average cost of maintenance for Haemodialysis machines and ensure their high operational availability, a Cost-Model is derived, and Genetic Algorithm is employed for optimization in this work. The application of RCBM strategy results in cost saving of about 60% of the cost incurred using current maintenance scheme. Statistical and optimization calculations are performed using Reliasoft's Weibull++ and MATLAB tools respectively.