The LED status indicator is continuously on red, indicating that the CO2 concentration is too high, and it also indicates that the ambient ventilation is insufficient. It is recommended to increase the indoor and outdoor fresh air convection, so that the outdoor fresh air can dilute the indoor CO2 concentration, which can reduce the indoor CO2 concentration, thereby making the LED indicator light turns yellow or green

≧　15 years.

Qui Vive is factory calibrited.  However , it should be recalibriated regularly to ensure good sensor reading. (note: sensors drift due to component aging, mishandling or prolong storage and etc) An internal calibration procedure is performed to bring the data back to the factory accuracy range.

Qui Vive emits a warning sound to indicate that the environment is poorly ventilated. It is recommended to perform indoor ventilation to reduce the ambient CO2 concentration, or press the mute button at the rear of Qui Vive to cancel the alarm sound state.

Currently using a one-to-one design; one Qui Vive can only be connected to one mobile device.

The buzzer is not linked with the LED status indicator. When the CO2 value is higher than the warning value, the LED will continue to light up red, until the value is lower than the warning value, it will turn to yellow or green.

Qui Vive CO2 Sensor is a USB type CO2 gas sensor. The USB power supply design allows users to detect CO2 concentration in a variety of occasions, including office/classroom/bedroom/ vehicle applications and so on.