Sampling for Industrial Testing
Why a sample must represent the lot, process or material question being asked.
What this topic covers
Why a sample must represent the lot, process or material question being asked.
Core testing ideas
Sampling can introduce more error than the laboratory test if the sample is not representative.
Random, systematic, stratified and targeted sampling answer different questions.
Prescriptive sampling plans depend on product risk, standards and customer requirements.
Measurement and method limits
A result is only meaningful when the characteristic, units, method and acceptance requirement are clear.
Evidence and traceability
Traceability and documentation let later reviewers understand what was tested and with which equipment and method.
Using the result
Inspection plans should focus effort on meaningful characteristics instead of collecting data without a decision path.