Calibration and verification both share the common goal of ensuring a function is working as expected. Particularly in regulated industries such as medical devices, manufacturing and laboratories. Although they relate to each other, they serve distinct purposes and involve different processes.
Depending on the type of device you use, both options have their place. However, it's important for device owners to understand the difference between the two. Along with their device's requirements to remain compliant and deliver accurate results.
What is calibration?
Calibration involves comparing a measuring instrument against a known standard and adjusting if deviations are found. Ensuring accuracy, traceability to national or international standards and long-term accuracy through periodic adjustments.
Using a UKAS accredited service provider is also an essential part of the calibration process. This ensures equipment is calibrated correctly and to the highest possible standard.
What are the key aspects of calibration?
- Reference standards – The device is compared against a traceable reference standard. For example, NIST, ISO, or national metrology institute standards)
- Adjustments – If discrepancies are found, the instrument is adjusted or corrected to ensure accurate measurements
- Traceability – Calibration must be traceable to an internationally recognised standard
- Certification – A valid calibration certificate is issued. Detailing before and after values, measurement uncertainty and corrections applied. Without this, outcomes could be dubious and not stand in a legal setting.
When is calibration needed?
- Scheduled maintenance – Regularly, as per the manufacturer’s guidelines or industry standards
- After repairs or adjustments – If a device has been repaired or serviced
- Before use in critical applications – When high accuracy is required, such as in medical device testing
- If measurement accuracy is suspected to be off – If inconsistent or unexpected results occur.
What is verification?
In contrast, verification is the process of checking whether an instrument meets predefined specifications without adjusting. Typically, someone performs this before use.
Verification generally entails employing an electro-acoustic ear simulator to compare it against a prior reading. No absolute measurement exists, only a reference point. These are typically conducted on a daily or weekly basis.
What are the key aspects of verification?
- Pass/Fail check – The device is tested to determine if it falls within acceptable tolerance limits
- No adjustments – Unlike calibration, verification does not involve corrections; it simply confirms if the instrument is performing correctly
- Conformity assessment – If the device does not meet the required standard, it may need recalibration or repairs.
When is verification needed?
- Before daily or routine use – Ensuring an instrument is working properly before measurements
- After transport or environmental changes – Checking accuracy after moving a device to a new location.
- During quality audits – Verifying compliance with industry standards (e.g., ISO 13485 for medical devices).
Calibration and verifications services
Instrument owners require a combination of both processes for consistent and safe performance. Using both reduces errors, improves quality and maintains regulatory compliance (e.g., ISO 13485, IEC 60601 for medical devices).
At Amplivox, we offer instrument calibration for audiometers. Along with verification for electroacoustic ears and spirometers.
To know more about our calibration and verification services, you can visit our services webpage. You can also contact our customer support team at +44 (0)1865 880 846. Alternatively, you can email us for more information.
References
International Organization for Standardization (ISO). Accessed at: https://www.iso.org/
National Institute of Standards and Technology (NIST). Accessed at: https://www.nist.gov/