Metrological traceability for measuring Indoor Air Quality using low-cost sensors

Indoor air quality (IAQ) monitoring has gained significant attention due to its impact on human health. Low-cost sensors allow widespread data collection but often lack proper characterisation and standard validation, affecting reliability. The Italian PRIN project "MIRABLE” - Measurement Infrastructure for Research on heAlthy and zero energy Buildings in novel Living lab Ecosystems - led by Italian National Metrology Institute, INRiM, and the Politecnico di Torino, aims to develop a measurement infrastructure for monitoring multi-domain indoor environmental conditions using low-cost sensors. In this framework INRiM started activities on the metrological characterization of low-cost sensors for CO2, CO, NOX. For CO₂ sensors, a calibration system using reference gas mixtures ensures metrological traceability, employing a primary reference analyser based on non-dispersive infrared spectroscopy. Exploratory findings and preliminary results with CO2 sensors are detailed in this work and a similar approach is planned for CO and NOX sensors.