Problem

• Heart rate data is still generated when the user's watch/band is not worn.
• The heart rate indicator on the back of the user's watch/band lights up when the device is not worn.

Cause

• Wearable devices use their optical heart rate sensor to collect optical signal fluctuations for heart rate calculations. However, optical signal fluctuations are everywhere in daily life. For example, fluorescent lamps operate at a frequency of 50 Hz, causing the light to flicker. There's a small chance that such fluctuations may be detected by the wearable's sensor, causing the system to misjudge them as signal changes of the human body. As a result, heart rate data may be generated even when the device is not worn.

Measurement mechanism:

The optical heart rate sensor on the back of the wearable device emits light and receives reflected light to detect capillary expansion and contraction due to heart beats. The corresponding optical signal fluctuations are collected and analyzed for the calculations of heart rate data.

Heart rate data and measurement results from wearable devices are for reference only and are not intended for medical use.

• If you have enabled the Continuous heart rate monitoring feature in the Huawei Health app on your phone or the smart measurement feature in the Heart Health Study app, your wearable will search for heart rate signal on a continual basis. In this case, if the device's heart rate sensor is obstructed (for example, in a bag or on a cotton quilt) or exposed to special lighting conditions, the device may incorrectly assume it's being worn and activate the heart rate indicator.

Solution

• All wearable devices with optical heart rate sensors face this issue. To minimize misjudgments, HUAWEI wearables have employed targeted algorithms for wearing detection and liveness detection. We will continually optimize these algorithms to enhance measurement accuracy. Please stay tuned for system updates and update your device at your earliest convenience.
• If you don't plan to use your wearable for an extended period of time, it is recommended that you place it on a table with its back facing up and unobstructed. Alternatively, you're advised to power off your wearable to prevent the heart rate indicator from activating.