1. Define the Calibration Scope Before Scheduling

Clear scope definition is the most critical step in preparing for onsite calibration.

Before the visit, confirm:

• Instruments requiring calibration
• Measurement ranges and tolerances
• Applicable standards (ISO/IEC 17025, ANSI/NCSL Z540.1, NIST traceable, or customer-specific requirements)
• As-found and as-left data expectations
• Adjustment and repair authorization

Provide complete instrument details, including manufacturer, model number, serial number, and internal asset ID. This ensures the calibration laboratory arrives with the correct standards and procedures.

2. Control Environmental Conditions

Calibration accuracy depends on environmental stability.

Prior to the onsite visit:

• Verify temperature and humidity meet calibration requirements
• Allow instruments to thermally stabilize
• Minimize vibration, airflow, and radiant heat sources

Calibrating equipment under controlled and representative conditions improves measurement reliability and audit defensibility.

3. Ensure Equipment Is Accessible and Clean

Onsite calibration efficiency depends on safe, unobstructed access.

Prepare work areas by:

• Clearing benches and instrument surroundings
• Removing parts, fixtures, and stored materials
• Cleaning contact surfaces such as anvils, probes, jaws, and platens
• Providing required power, compressed air, or network access

Routine pre-cleaning reduces false failures caused by contamination rather than true out-of-tolerance conditions.

4. Address Out-of-Tolerance Risk Proactively

If an instrument may be out of tolerance:

• Communicate concerns before the visit
• Define adjustment or repair authorization
• Confirm decision rules for pass/fail determinations

Clear direction prevents delays and ensures consistent disposition in accordance with standards and internal quality procedures.

5. Assign a Knowledgeable Point of Contact

Designate a primary onsite contact who can:

• Answer technical and procedural questions
• Authorize adjustments or repairs
• Provide access to quality records and procedures

Availability of a qualified contact reduces assumptions and keeps the calibration process moving efficiently.

6. Prepare Calibration Records and Labels

Have the following documentation readily available:

• Previous calibration certificates
• Internal calibration procedures, if applicable
• Asset lists and recall schedules
• Calibration status labels or tagging requirements

Clear expectations for labeling and documentation help ensure consistent recordkeeping and compliance.

7. Plan Around Production and Laboratory Operations

Even onsite calibration requires coordination.

• Schedule critical instruments during planned downtime when possible
• Identify backup equipment
• Notify operators and lab personnel in advance

Proper planning protects measurement integrity and minimizes operational impact.

8. Review Calibration Results Immediately

After the onsite calibration is completed:

• Review certificates for completeness and compliance
• Verify traceability statements and uncertainty reporting
• Confirm internal asset systems reflect updated calibration status

Prompt review allows discrepancies to be resolved quickly and maintains confidence in calibration data.

Conclusion

Onsite calibration should be treated as a controlled quality activity—not a reactive task. Proper preparation improves efficiency, reduces risk, and ensures calibration results withstand internal audits, customer requirements, and third-party assessments.

Bagan Calibrations, a division of Richard J. Bagan, Inc., provides onsite calibration services designed to integrate seamlessly into ISO/IEC 17025 and ANSI/NCSL Z540-compliant quality systems. Successful onsite calibration begins with informed preparation.

For questions about onsite calibration planning or scope development, contact Richard J. Bagan, Inc. to speak directly with a metrologist.