Air quality sensors are devices that measure and monitor the composition of pollutants in the air. They can detect gases like carbon monoxide, nitrogen dioxide, ozone, and volatile organic compounds (VOCs) as well as particles like dust, smoke and pollen. Air quality sensors help detect potential air quality problems, such as high levels of pollution, and can also be used to detect dangerous levels of specific toxins. Many types of air quality sensors are available, including electrochemical, semiconductor, infrared, and ultraviolet sensors. Some sensors are used to monitor indoor air quality, while others are designed to measure outdoor air quality. Air quality sensors can be used in a variety of applications, from industrial monitoring to public health monitoring.