Measurement System Analysis and Maintenance Guide
Measurement system analysis ensures that measurement systems are adequate for their intended use. A well-maintained system provides reliable data for process control and quality decisions.
I. Measurement System Analysis
- Gauge Repeatability and Reproducibility: Evaluate the variation contributed by the measurement equipment (repeatability) and different operators (reproducibility). The combined variation should be less than ten percent of the process tolerance for critical measurements.
- Linearity: Verify measurement accuracy is consistent across the entire measurement range
- Stability: Monitor measurement drift over time using control charts with reference standards
- Bias: Compare average measurements against a certified reference value to quantify systematic error
II. Calibration Management
- Maintain a calibration schedule for all measurement equipment
- Use calibration standards with valid traceability to national or international standards
- Define calibration intervals based on equipment stability, usage frequency, and criticality
- Document all calibration results including as-found and as-left values
III. System Maintenance
- Establish a preventive maintenance schedule for all measurement system components
- Monitor environmental conditions (temperature, humidity, vibration) that affect measurement accuracy
- Train operators on proper measurement techniques and equipment handling
- Investigate and resolve any out-of-control conditions identified through measurement system monitoring
