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Disclaimer: Due to health regulations and clearances, some ScanWatch features may not be available or may not have clinical validation in your region. Learn more.

The result of a one-time measurement with ScanWatch depends on the measurement conditions. Performing multiple measurements allows you to better monitor SpO2 by creating a trend.

To make sure that the measured value is as close as possible to the real physical value, or if the measurement is qualified as "inconclusive", make sure that your watch is correctly positioned and tightened, and that your gesture follows these best practices.

Watch positioning

  1. Place your watch on your non-dominant wrist, 1 cm from the wrist bone.
  2. Make sure that your ScanWatch is not loose on your wrist. Tighten the band until it is snug but comfortable. When the watch moves, your skin should move along with it.
  3. Wearing the watch closer to the elbow can help you to obtain a better fit.

How to perform an accurate SpO2 measurement

  1. Make sure to wear the watch at least 3 to 4 minutes before the measurement.
  2. Make sure you have been resting for at least 10 minutes after your last workout session.
  3. Rest your arm on a table, with the hand relaxed and in an open position.
  4. Press the side button of the watch and scroll to the SpO2 mode. Press the button to select the SpO2 mode.
  5. Push lightly on the top of the watch with your other hand to improve the contact between the skin and the watch, making sure that the bottom of the watch remains flush with the skin.
  6. Do not move or speak for the 30 seconds necessary to take the measurement.
  7. Low pulsatile signal often occurs when your hands and/or arms are cold. In this case, rubbing the skin that will be in contact with or around the sensor may help.


  • Even under ideal conditions, a SpO2 measurement may not be conclusive. An inconclusive result may be caused by an inaccurate data or an element affecting the process.
  • For best results, we recommend using the fluoroelastomer wristband provided with ScanWatch.


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