A component of total productive maintenance (TPM) that measures how effectively equipment is being used.
OEE is calculated using three elements: availability represents losses in downtime due to outages and equipment adjustments as a percentage of scheduled time. Productivity expresses losses in speed - when the process is slower than its intended speed and interruptions last a few seconds. Quality expresses losses due to downtime and repairs as a percentage of total parts processed.
To calculate OEE, these three elements are multiplied by each other:
Availability × productivity × quality = OEE
If availability is 90%, productivity is 95% and quality is 99%, the following percentage emerges:
0.90 × 0.95 × 0.99 = 84.6% OEE
OEE typically focuses on what are considered the six biggest losses: breakdowns, turnarounds, short stops, slower speed, downtime and repair work. However, some companies add other elements they consider important to their business.