Conformity assessment of a multi-sensor device for indoor environmental quality monitoring

The monitoring and control of thermal, visual, acoustic and air quality conditions in an indoor environment is important due to the influence they have on people's health, comfort and productivity. This work presents the second step of the metrological characterization of ten prototypes of a low-cost multi-sensor device, designed and developed to monitor air temperature, relative humidity, illuminance, sound pressure level, carbon monoxide, carbon dioxide, particulate matter, formaldehyde, volatile organic compounds and nitrogen dioxide. The set of low-cost sensors embedded in this device, referred to as PROMET&O (PROactive Monitoring for indoor EnvironmenTal quality & cOmfort), was previously tested against reference laboratory-grade devices after the definition of measurement requirements. The specifically conceived calibration procedures were tailored to the requirements of each measurement quantity and applied to the bare sensors. The results of this work show the application of the same identified methodologies to the assembled multi-sensor, with the aim of analyzing the mutual influences of the hardware components included in the device, and the effects of the external case and the sensors allocation.