Six Big Losses
The Six Big Losses are common categories of production loss affecting equipment availability, performance, and quality.
What this term means in maintenance
The Six Big Losses are common categories of production loss affecting equipment availability, performance, and quality.
The Six Big Losses
The traditional categories are:
- Equipment failures
- Setup and adjustment
- Idling and minor stops
- Reduced speed
- Process defects
- Reduced yield during startup
Relationship to OEE
The losses influence the three OEE components:
- Availability: failures, setup, and adjustment
- Performance: minor stops and reduced speed
- Quality: defects and startup losses
Practical example
A packaging line has acceptable breakdown time but poor OEE. Review shows frequent two-minute sensor stops and reduced running speed. The main opportunity is performance loss rather than major maintenance downtime.
Why the categories help
They create a shared language for maintenance, production, quality, and engineering to identify where output is being lost.
Common mistake
Recording only major breakdowns ignores minor stops, speed loss, and quality loss that may create a larger total impact.
Related concepts
Related maintenance terms
Keep exploring connected CMMS, reliability, and maintenance planning terms.
Overall Equipment Effectiveness
Overall Equipment Effectiveness, or OEE, measures how effectively planned production time is converted into good output by combining availability, performance, and quality.
Equipment Downtime
Equipment downtime is the period when an asset is required or scheduled to operate but is unavailable or unable to perform its intended function.
Total Productive Maintenance
Total Productive Maintenance, or TPM, is a company-wide approach to improving equipment effectiveness through operator involvement, planned maintenance, quality control, training, and continuous improvement.
Glossary FAQs
- What are the Six Big Losses?
Equipment failures, setup and adjustment, idling and minor stops, reduced speed, process defects, and startup yield loss.
- How are the Six Big Losses related to OEE?
They contribute to availability, performance, and quality losses.
- Are all Six Big Losses caused by maintenance?
No. Operations, process, materials, quality, engineering, and maintenance can all contribute.