MSA Basics

Question 1

What is bias and measurement system

A. Random variation
B. Operator preference
C. Systematic error
D. Equipment wear

Answer 1

C. Systematic error

Bias is the difference between the observed average of measurements and the reference value. It represents systematic error or consistent deviation from the true value

Question 2

What does linearity and MSA measure

A. Straight line measurements
B. Change and bias across measurement range
C. Time between measurements
D. Operator consistency

Answer 2

B. Changing bias across measurement range

Linearity measures how bias changes across the expected operating range of the measurement system. It shows if accuracy is consistent across different sizes or values being measured

Question 3

What does stability and MSA measure

A. Variation and single measurements
B. Variation between instruments
C. Stability of operators while taking measurements
D. Variation over time

Answer 3

D. Variation over time

Stability measures how consistent measurements remain overtime when measuring the same part. It helps identify if the measurement system is drifting or changing over time

Question 4

What is reproducibility in MSA

A. Equipment variation
B. Parts apart variation
C. Operator to operator variation
D. Time-based variation

Answer 4

C. Operator to operator variation

Reproducibility is the variation and average measurements made by different operators using the same measuring instrument when measuring identical characteristics on the same part

Question 5

What is repeatability and MSA

A. Variation and measurements when the same operator and instrument measure the same part multiple times
B. Variation and measurements between different operators using the same instrument
C. The ability of the system to measure different parts consistently
D. The tendency of an instrument to drift over time

Answer 5

A. Variation and measurements when the same operator and instrument measure the same part multiple times

Repeatability assesses how consistently a measurement device gives the same reading when measuring the same part under identical conditions

Question 6

What percentage of total variation should an acceptable gauge are in our study have

A. Less than 10%
B. Between 20 and 30%
C. More than 50%
D. At least 99.99%

Answer 6

A. Less than 10%

A gauge R&R study shows ideally contribute less than 10% of the total variation in a process to ensure measurement reliability if the variation exceeds 30%, the measurement system may not be suitable

Question 7

According to the rule of 10, if a part tolerance is 0.5 mm, what should the minimum resolution of the measuring instrument

A. 0.05 mm
B. 0.5 mm
C. 0.05mm
D. 0.1 mm

Answer 7

A. 0.05 mm

Per the role of 10 to resolution should divide the tolerance into 10 parts so 0.5 mm/ 10 = 0.05 mm resolution

Question 8

Why is 5.15 Cigna used instead of six sigma in p/t calculations

A. To make calculations easier
B. To be more conservative
C. To capture 99% of measurement variation
D. To capture 99.73% of measurement variation

Answer 8

C. To capture 99% of measurement variation

5.15 sigma is used because it captures 99% of the measurement variation which is considered sufficient and most industrial applications while six sigma + -3 captures 99.73

Question 9

If reproducibility is poor, what does this suggest

A. The measurement instrument is defective
B. The process variation is too high to be measured
C. Operators influence the measurement process significantly
D. The instrument needs more resolution

Answer 9

C. Operators influence the measurement process significantly

Poor reproducibility means that different operators are obtaining different results with the same instrument indicating and consistency and operator technique or lack of standardized measurement procedures