In laboratories and industrial environments, accurate measurements are essential for quality control,
regulatory compliance,
and reliable testing results. When equipment begins to produce inaccurate readings, the terms calibration and adjustment are often used interchangeably. However, these two processes serve different purposes.
Understanding the difference between calibration and adjustment can help laboratories and facilities maintain accurate equipment and ensure measurements remain within acceptable tolerances.
What Is Calibration?
Calibration is the process of comparing a measurement device to a known reference standard to determine how accurate the instrument is.
During calibration, a technician measures the device’s performance using traceable standards and records the difference between the instrument’s reading and the known reference value.
Calibration itself does not change the instrument’s settings. Instead, it documents how accurate the equipment currently is.
Calibration results typically include:
• measured values compared to known standards
• measurement uncertainty
• documentation for quality systems or audits
Calibration ensures that equipment accuracy can be verified and traced back to national or international standards.
What Is Adjustment?
Adjustment is the process of correcting the instrument so that it produces more accurate readings.
If calibration reveals that an instrument is outside acceptable tolerance, adjustment may be performed to bring the equipment back within specification.
Adjustment may involve:
• correcting internal settings
• recalibrating internal electronics
• adjusting mechanical components
After adjustment, the instrument is typically calibrated again to confirm that it now meets required accuracy specifications.
Why the Difference Matters
Understanding the difference between calibration and adjustment is important for maintaining reliable measurement systems.
Calibration provides documentation of accuracy, while adjustment corrects any errors found during calibration.
Many quality systems require calibration records even when no adjustment is necessary. This documentation proves that equipment was verified and operating correctly at the time of testing.
Regulatory and Quality System Considerations
Laboratories and facilities operating under quality standards must maintain proper calibration documentation.
Standards such as ISO 17025 require laboratories to demonstrate that measurement equipment is calibrated using traceable standards.
In regulated industries such as pharmaceuticals, biotechnology, and manufacturing, calibration records are often reviewed during inspections and audits.
Maintaining accurate calibration documentation helps ensure equipment performance can be verified and trusted.
Many laboratories also rely on accredited calibration providers to support compliance with these requirements. Accreditation bodies such as A2LA (American Association for Laboratory Accreditation) verify that calibration providers meet strict technical and quality standards.
Working with an accredited provider helps ensure that calibration results are accurate, traceable, and accepted during audits.
When Adjustment May Be Needed
Adjustment may be necessary if calibration reveals that an instrument is outside acceptable tolerance.
Common causes include:
• normal instrument drift over time
• environmental changes
• heavy usage
• mechanical wear
• improper handling or transport
Regular calibration helps identify these issues early so that adjustments can be made before inaccurate measurements affect results.
The Importance of Routine Calibration
Routine calibration ensures that laboratory and industrial equipment continue to perform within required accuracy limits.
Benefits of regular calibration include:
• improved measurement accuracy
• documented compliance for audits
• early detection of equipment issues
• increased confidence in measurement results
Establishing a consistent calibration schedule is one of the most effective ways to maintain reliable equipment performance.
Need Help With Calibration Services?
If your laboratory or facility relies on accurate measurement equipment, routine calibration is essential to maintain performance and compliance.
The technicians at The Lab People and The Scale People provide professional calibration services for a wide range of laboratory and industrial equipment.
To learn more about our calibration services or to schedule service, contact us today to speak with our team.
Bringing It All Together
Calibration and adjustment are related but distinct processes. Calibration verifies the accuracy of an instrument, while adjustment corrects errors that may be discovered during calibration.
By understanding the difference and maintaining regular calibration schedules, laboratories and facilities can ensure accurate measurements, reliable data, and continued compliance with quality standards.