Calibration Constancy Intercomparison System for Microwave Oven Survey Instruments
This guidance outlines procedures for establishing and maintaining a calibration constancy intercomparison system for microwave oven compliance survey instruments. It aims to ensure proper calibration of instruments used in production testing and quality control programs to verify compliance with the Federal Performance Standard for Microwave Ovens (21 CFR 1030.10).
Recommended Actions
- Establish calibration constancy intercomparison system with required components
- Implement daily check program:
- Check polarization response before use
- Document results for each instrument
- Remove failed instruments from service
- Implement monthly check program:
- Verify reference field constancy
- Check compliance instruments against 10% criteria
- Perform 2 dB comparison checks
- Maintain required documentation
- Set up annual calibration schedule:
- LCR absolute calibration
- Other instruments as recommended by manufacturers
- Create documentation system:
- Daily check records
- 30-day instrument comparison logs
- 12-month historical records
- Calibration and repair records
- Establish procedures for:
- Handling failed instruments
- Repair and recalibration processes
- Record renewal requirements
- Train personnel on:
- System operation
- Check procedures
- Documentation requirements
- Failure response protocols
Key Considerations
Non-clinical testing
- Daily checks of polarization response required before instrument use
- Monthly checks of reference field and compliance instruments required
- Annual absolute calibration of Local Calibration Reference (LCR) required
- Periodic recalibration (every 3 years) of all compliance instruments recommended
Safety
- Polarization ellipticity error must meet manufacturer specifications
- Reference field readings must agree within 10% between checks
- Survey instruments must maintain readings within 10% between checks
- Maximum 2 dB difference allowed between most and least sensitive instruments
Other considerations
- System requires microwave source, radiated power monitor, anechoic environment, and local calibration reference
- Detailed documentation required for all checks and calibrations
- Specific procedures for repair and recalibration after failures
- Temperature monitoring during checks recommended
Related references and norms
- 21 CFR 1030.10: Federal Performance Standard for Microwave Ovens
Original guidance
- Calibration Constancy Intercomparison System for Microwave Oven Survey Instruments
- HTML / PDF
- Issue date: 1988-03-01
- Last changed date: 2018-12-01
- Status: FINAL
- Official FDA topics: Medical Devices, Radiation-Emitting Products, Radiological Health
- ReguVirta summary file ID: f80c2108459deda38765af327c574aeb
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