I. Pre-calibration Preparation
1. Check device status: Ensure the battery is sufficiently charged, the cuff is free of damage or leaks, and the air tube is securely connected without kinks.
2. Set up the calibration environment: Choose a quiet space with an ambient temperature of 20–25°C and no strong electromagnetic interference; sit quietly for 5–10 minutes beforehand.
II. Simple Home Self-Check Calibration
1. Verification via repeated measurements: Measure blood pressure three times consecutively with 2-minute intervals; the difference between readings should normally be less than 5 mmHg. Excessive fluctuation indicates a potential issue.
2. Comparison with medical-grade equipment: Take the device to a medical facility and perform simultaneous measurements alongside a calibrated mercury sphygmomanometer; the device passes if the difference remains within ±5 mmHg across three consecutive readings.
3. Device reset: Press and hold the power button for 10 seconds to restore factory settings; some high-end models allow entry into self-calibration mode (refer to the manual) to perform zero-point calibration.
III. Professional Calibration Methods
1. Manufacturer/Brand service calibration: Contact the official after-sales service; professionals will test the device using a standard pressure generator and adjust internal parameters to keep the error margin within ±3 mmHg. This is the most reliable calibration method.
2. Metrology agency calibration: Send the device to a testing agency with CMA (China Metrology Accreditation) certification for compliance testing; some community health service centers also offer basic calibration services.
IV. Key Precautions
1. Do not disassemble the device or adjust internal components yourself to avoid damaging precision sensors, which could cause permanent measurement errors.
2. Professional calibration is recommended every 6–12 months; accuracy verification is mandatory before reusing the device after a long period of inactivity.
3. Recalibration is required after replacing the cuff to prevent changes in pressure transmission from affecting measurement results.
