# The Human Performance Impact on OEE in the Adoption of New Production Technologies
## 3 Framework Proposal
### Proposal of the OEE Measurement Methodologies
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt}} \hline \hline
**Parameter** & **Definition** \\ \hline Production time (PT) & Sum of all the machine processing times \\ \hline Idle time (IT) & Unplanned machine minor stops and slowdown times \\ \hline Blocking time (BT) & Unplanned stop time due to a block of the downstream operations sequence \\ \hline Starving time (ST) & Unplanned stop time due to a lack of materials \\ \hline Fauulted time due to the process (Fproc) & Sum of all the major stops attributable to human errors or to process configuration errors \\ \hline Fauulted time due to the machinery (Fmac) & Sum of all the major stops attributable to the machinery errors \\ \hline Operator maintenance (OM) & Unplanned time in which the operator performs maintenance \\ \hline Setup time (ST) & Sum of time for setups and changeovers \\ \hline Non-compliant products due to the process (\(\text{P}_{\text{nc, proc}}\)) & Number of products that need rework due to human error or due to process configuration \\ \hline Non-compliant products due to the machinery (\(\text{P}_{\text{nc, mac}}\)) & Number of products that need rework due to machinery errors \\ \hline Potential products due to the process (\(\text{P}_{\text{pot, proc}}\)) & Number of additional obtainable products in a fully operational state with the absence of human-process errors \\ \hline Potential product due to the machinery (\(\text{P}_{\text{pot, mac}}\)) & Number of additional obtainable products in a fully operational state with the absence of machine errors \\ \hline Uptime (U) & Sum of production time, idle time, blocking time and starving time \\ \hline Downtime (D) & Sum of faulted time, operator maintenance and setup time \\ \hline Compliant products (\(\text{P}_{\text{c}}\)) & Number of products that do not need reworking \\ \hline Non-compliant products (\(\text{P}_{\text{nc}}\)) & Number of products that need reworking, either for human-process errors or for machinery errors \\ \hline Potential products (\(\text{P}_{\text{pot}}\)) & Sum of additional obtainable products in a fully operational state with the absence of human-process and machinery errors \\ \hline Target products (\(\text{P}_{\text{target}}\)) & Sum of compliant products, non-compliant products and potential products \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Definition of metrics used for the OEE evaluation methodology. In light of these assumptions, it is possible to observe that the measurement methodology is derived from the calculation through the elimination of human-process inefficiencies. Considering the previous table, it is clear that \(\text{OEE}_{\text{proc}}\) evaluates all possible inefficiencies, including human errors, process configuration errors and losses attributable to the machinery. Differently, \(\text{OEE}_{\text{mac}}\) separates and recovers the factors attributable to an incorrect configuration of the process and human errors as additional processing times. The differentiation of the OEE measurement methodologies allows the real inefficiencies of the production technology to be isolated, assuming that human errors and process configuration errors are avoided. For this reason, the \(\text{OEE}_{\text{mac}}\) value is always greater than the \(\text{OEE}_{\text{proc}}\) value. Note that the added value of these measurement methodologies lies in the distinction between the losses of efficiency caused by human-process configuration errors and the ones caused by the machinery errors. This is obtained by the inclusion of potential products (\(\text{P}_{\text{pot}}\)) and in the distinction between non-compliant products due to human-process errors (\(\text{P}_{\text{nc, proc}}\)) and non-compliant products due to machinery errors (\(\text{P}_{\text{nc, mac}}\)) within the OEE assessment, as well as the distinction between downtime due to human-process errors (\(\text{P}_{\text{proc}}\)) and due to machinery errors (\(\text{F}_{\text{mac}}\)).