6 Big Losses in Equipment Efficiency

The 6 Big Losses are a way to categorize equipment-based productivity losses in manufacturing environments. They are:

equipment failure (breakdown) loss: The largest of all losses, it includes significant periods of time equipment is scheduled for production but is not running due to unplanned events such as tool failures, unplanned maintenance, upstream / downstream blockages, etc.
set-up and adjustment loss: Losses due to (planned) downtime from changeover and minor process adjustments.
speed loss: When equipment runs slower than the ideal cycle time due to poor conditions, operator inexperience, inadequate lubrication, etc.
minor stoppage and idling loss: Small stops that account for short periods of time when the equipment is not running in order to address things like clearing a jam, changing a setting or hanging a part. Small stops are typically remedied by the operator within a few minutes.
defect and rework loss: This loss accounts for the production of defective parts that are scrapped or that require rework. These losses typically occur during steady-state production and are caused by operator error, equipment handling, or incorrect equipment settings.
start-up / yield loss: Losses that occur during equipment warm-up, or after a restart post changeover before the machine has reached stable production.

TPM (Total Productive Maintenance) and OEE (Operating Equipment Effectiveness) focused programs are often implemented to reduce and / or eliminate the 6 Big Losses.