CCT CCT Quality Management & Documentation 2 — Questions and Answers
Question 1: What is 'measurement uncertainty' as used in calibration documentation?
- The probability that equipment will fail
- A quantified doubt about the validity of a measurement result (Correct answer)
- The difference between two calibration dates
- A measure of technician skill level
Correct answer: A quantified doubt about the validity of a measurement result
Measurement uncertainty is a parameter that characterizes the dispersion of values that could reasonably be attributed to the measurand, quantifying the doubt about the measurement result.
Question 2: Which US federal agency provides the national measurement standards that calibration traceability chains reference?
- EPA
- OSHA
- NIST (Correct answer)
- FDA
Correct answer: NIST
The National Institute of Standards and Technology (NIST) is the US federal agency responsible for maintaining national measurement standards to which calibration traceability is established.
Question 3: What is the purpose of a 'calibration interval'?
- The time between equipment purchases
- The scheduled period between successive calibrations to ensure ongoing accuracy (Correct answer)
- The time it takes to perform a single calibration
- The gap between receiving calibration equipment and using it
Correct answer: The scheduled period between successive calibrations to ensure ongoing accuracy
A calibration interval defines the maximum time between calibrations, determined by factors such as instrument stability, usage conditions, and required measurement accuracy.
Question 4: In a quality management system, what is the role of an 'audit trail' in calibration records?
- To track financial transactions related to calibration
- To provide a chronological record of changes to documents and data (Correct answer)
- To list all approved vendors
- To schedule employee performance reviews
Correct answer: To provide a chronological record of changes to documents and data
An audit trail in calibration records provides a chronological, tamper-evident history of all changes to calibration data and documents, supporting accountability and traceability.
Question 5: What does a 'Test Uncertainty Ratio' (TUR) of 4:1 mean in calibration quality standards?
- Four technicians are needed for each calibration
- The reference standard is four times more accurate than the device under test (Correct answer)
- Four calibrations are performed per year
- The calibration takes four hours to complete
Correct answer: The reference standard is four times more accurate than the device under test
A TUR of 4:1 means the measurement uncertainty of the reference standard is at least four times smaller than the tolerance of the device under test, providing adequate calibration confidence.
Question 6: Which element is required on a calibration label affixed to calibrated equipment?
- Equipment purchase price
- Calibration due date or next calibration date (Correct answer)
- Name of the laboratory director
- Customer billing information
Correct answer: Calibration due date or next calibration date
Calibration labels must display at minimum the calibration date and the next due date so users can quickly determine if the instrument is currently within its calibration interval.
CCT CCT Quality Management & Documentation 2
What is 'measurement uncertainty' as used in calibration documentation?