What is the purpose of calibration of inspection tools?

• A. To reduce tool cost
• B. To extend battery life
• C. To improve visual appearance of instruments
• D. To ensure measurement accuracy and traceability to standards

Answer: (D)

Calibration ensures that measurement tools provide readings that reflect true values within specified tolerances and that those readings can be traced back to recognized standards. Over time, instruments can drift due to wear, temperature, or use. By comparing the tool against known reference standards and making any necessary adjustments, you establish accuracy and create a documented record (calibration certificate) showing the instrument’s performance and its measurement uncertainty. This traceability to standards is what lets measurements be trusted, compared over time, and used to demonstrate compliance with quality requirements. The other options aren’t about accuracy or reference to standards—calibration isn’t primarily for reducing cost, extending battery life, or improving appearance.