Glossary

measurement system

A measurement system is the combined method, equipment, software, people, and procedures used to obtain and record measurements.

Audit and Compliance Readiness (AS9100, LPAs and Process Audits)

A measurement system is the complete set of elements used to generate a measurement result. It commonly includes the measuring instrument or sensor, the method of measurement, the software or data collection tools, the operator, the environment, and the procedures used to collect, calculate, record, and interpret the value.

In manufacturing and regulated operations, the term is broader than a single gage or device. A caliper, CMM, vision system, weigh scale, temperature probe, or inline sensor may be part of a measurement system, but the system also includes how the measurement is taken, under what conditions, by whom, and how the result is stored or used.

What it includes

Measurement equipment such as gages, sensors, test instruments, or inspection machines
Fixtures, reference standards, and calibration status
Methods, work instructions, and acceptance criteria
Operators or inspectors and their technique
Software, data interfaces, and recordkeeping used to capture results
Environmental conditions that can affect results, such as temperature, vibration, humidity, or lighting

Operational meaning

Measurement systems appear anywhere a process needs data to verify product conformance, monitor process performance, or support release and traceability records. Examples include in-process dimensional checks on a machining line, automated torque measurement at assembly, or environmental monitoring recorded in MES or quality systems.

Because decisions are made from the data, the reliability of the measurement system matters. In practice, organizations often evaluate whether the system is stable, accurate enough for its intended use, and capable of producing repeatable and reproducible results. This is why the term is often discussed alongside measurement system analysis, gage R&R, calibration, and metrology.

Common confusion

Measurement system is often confused with measuring device or gage. A device is only one component of the full system.

It is also commonly confused with measurement system analysis (MSA). MSA is the evaluation of a measurement system’s performance, not the measurement system itself.

In some contexts, people use the term to mean a unit convention such as metric or imperial. That meaning exists in general language, but in manufacturing and quality contexts, measurement system usually refers to the full arrangement used to produce measurement data.

Yes. AI can be used to support aerospace inspection planning, but it does not remove requirements for approved inspection criteria, traceability, change control, validation, customer flow-downs, or human accountability. Constraints depend on the part, program, quality system, data controls, and how the AI output is used.

Do MRO organizations always need AS9100, or is AS9110 more suitable?

MRO organizations do not always need AS9100. AS9110 is specifically written for aerospace maintenance organizations and is often more suitable when you primarily perform maintenance, repair, and overhaul rather than design or new production. Customer, contractual, and authority requirements ultimately determine what is acceptable.

What MRO records are auditors most likely to request during a Part 145 inspection?

Auditors in a Part 145 inspection usually ask first for records that prove control of work, personnel, parts, tooling, and release decisions. The exact mix varies by authority, ratings, scope, and recent findings, but you should expect requests for work orders, maintenance release evidence, training and authorization records, calibration, traceability, and records showing how discrepancies and changes were controlled.

How detailed does our risk register need to be for certification?

There is no single "correct" level of detail for a risk register that guarantees certification. Auditors expect a risk register to be complete, traceable, and justified relative to your processes, regulations, and quality system. Level of detail must be enough to show systematic identification, evaluation, control, and review of risks, without becoming unmaintainable or inconsistent across the plant.

Related Glossary