In the master thesis we have researched the problem of equipment efficiency in individual production. We have described the methods for recoginsing time losses on working tools, operational systems for recording working tools's functions and described the course of calculating equipment efficiency. With selected multimoment method (MNS) we have defined time structures of working tools and have recognised losses that accoure. With the collected data we calculated overall equipment efficiency (OEE). For comparison we collected function data from operation systems MES and SAP for all observed working tools and calculated the OEE with those data. From calculated OEE comparison we discovered that there is no consistency of recording working tools stoppage in the systems, therefore we can not get the real picture of working tools function. The second problem we noticed was the deviation among real used time on working tool and prescribed theoretical normed time. We have done the hi^2 -test with collected real and theoretical used times, to prove the statistical significant difference. In the conclusion we suggest a new program for recording stoppage on machine tools.