# CO2 RHT Module

This sensor module measures highly accurate CO2, relative humidity, and temperature. CO2 is a crucial indicator of indoor air quality (IAQ), as high levels compromise humans' cognitive performance and well-being. This module is compatible with relevant IAQ standards and has a high-accuracy measurement range of 400 – 5.000 ppm.

<figure><img src="/files/0TbJP2OGpnlXZdmsuiBA" alt="" width="375"><figcaption><p>CO2 RHT Module Front View</p></figcaption></figure>

## Sensor Module

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We refer to sensor manufacturers' datasheets to provide the specifications. The sensor readings may differ due to application, sensor aging, storage, transportation, environmental factors, factory calibration process, etc.
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### Sensirion SCD41 CO2 and RH\&T Sensor

SCD41 is Sensirion's next-generation miniature CO2 sensor. It builds on the photoacoustic NDIR sensing principle and Sensirion's patented PASens® and CMOSens® technology to offer high-accuracy CO2 readings and relative humidity and temperature measurements.

<table><thead><tr><th width="189">Measurement</th><th width="255">Accuracy</th><th width="132">Min</th><th>Max</th></tr></thead><tbody><tr><td>Temperature</td><td>± 0.8°C @ 15...35°C<br>± 1.5°C @ -10...60°C</td><td>-10°C</td><td>60°C</td></tr><tr><td>Relative Humidity</td><td>± 6% rH @ 15 °C – 35 °C, 20 %RH – 65 %RH<br>± 9% rH @ -10 °C – 60 °C, 0 %RH – 100 %RH</td><td>0% rH</td><td>100% rH</td></tr><tr><td>CO2</td><td>400 ppm ... 1000 ppm ±(50 ppm + 2.5% of reading)<br>1001 ppm ... 2000 ppm ±(50 ppm + 3% of reading)<br>2001 ppm ... 5000 ppm ±(40 ppm + 5% of reading)</td><td>400 ppm</td><td>5.000 ppm</td></tr><tr><td>Dew Point</td><td>N/A</td><td>-40°C</td><td>40°C</td></tr></tbody></table>

## Libraries and Samples

Some of our devices come with firmware that automatically utilizes the module without requiring any coding. For development kits or further customization, you may choose to use the following libraries and samples to create a custom application.

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