## 4 Method Development  
Based on the identified groups of losses, effectiveness indicators were developed for operators, logistics services, organizational services and maintenance services, as well as for the procedure of applying the method (Figure 2). The procedure assumes the use of the method for periodic evaluation, for identifying the source of problems, and for monitoring the impact of changes on the production process. The entire production line, or selected positions, as well as selected areas of responsibility or selected groups of losses, can be evaluated. It is recommended that the person conducting the assessment knows the process and the competencies required in its area. The assessment includes the measurement of production losses using an evaluation sheet adapted to the company's current standards. The results are presented in the form of effectiveness indicators and coefficients of availability, performance and quality, the analysis of which enables the identification of areas for improvement. The ratio of the actual effects to those that are achievable with the use of specific resources was adopted as the effectiveness indicators, with the inputs expressed in the form of the results planned to be achieved with the use of these resources. If the results are satisfactory, another assessment date is set. If it is necessary to implement improvements, the measurements are repeated, with the analysis of the recalculated coefficients and indicators allowing the impact of the introduced changes on the production process to be monitored and the next steps to be decided upon. The Operator Production Effectiveness indicator was determined as the product of Operator Availability, Operator Production Performance and Operator Production Quality, expressed as a percentage. \[OPE=A_{O}\times P_{O}\times Q_{O} \tag{1}\]  
_OPE:_ Operator Production Effectiveness  
\(A_{O}\): Operator Availability  
\(P_{O}\): Operator Production Performance  
\(Q_{O}\): Operator Production Quality  
The Operator Availability coefficient was defined as the ratio of the actual and assumed operator's working time, minus any losses beyond his/her control. A reduced value of the coefficient may indicate absenteeism at the position, excessively long times of production-related activities, and other downtime caused by the operator. To calculate the Availability coefficient, it is necessary to collect data (based on production records) on the total available time and the time of planned downtime during the time period considered for the study,  
Figure 2: Scheme of the procedure for applying the method. and then measure the times of unplanned downtime occurring at that time, separately due to the operator, separately independent of the operator. \[ \begin{array}{c}A_{O}=\frac{t_{O}}{t_{O}}\times 100\%=\frac{t_{O}-t_{O}}{t_{O}-t_{ al}}\\ \times 100\%=\frac{t_{O}-t_{ull}-t_{O}}{t_{t}-t_{uD}-t_{ull}}\times 100\%=\frac{t_{l}-t_{ p}-t_{ull}-t_{O}}{t_{t}-t_{uD}-t_{ull}}\times 100\%\end{array}  \tag{2}\]  
\(t_{O}\): actual operator working time  
\(t_{PO}\): possible operator working time  
\(t_{SO}\): unplanned operator downtime  
\(t_{tO}\): assumed operator working time  
\(t_{sl}\): time of unplanned downtime through no fault of the operator  
\(t_{t}\): total available time  
\(t_{sP}\): planned downtime  
The Operator Production Performance coefficient was defined as the ratio of the amount of production possible to be performed by the operator to the total possible production. A reduced value of the coefficient may indicate either the operator's failure to comply with certain work procedures, or a reduced ability to perform certain activities. To calculate the Performance coefficient, it is necessary to measure (in addition to the times collected during the measurements of availability) production delay time by the operator (e.g., caused by difficulties in using an inappropriate tool, performing activities in the wrong order, etc. ), which reduce the rate of production. The delay is calculated in relation to the theoretical cycle time. \[