One-Point Calibration of Low-Cost Sensors for Particulate Air Matter (PM) Concentration Measurement

Area of Science:

• Environmental Science
• Sensor Technology
• Automotive Engineering

Background:

• Low-cost sensors are increasingly used in automotive and building applications for environmental monitoring.
• Validating the accuracy of these low-cost sensors remains a significant challenge.
• Widespread deployment requires reliable data for energy control and air quality assessment.

Purpose of the Study:

• To propose and evaluate an innovative approach for verifying measurements from low-cost sensors in automotive applications.
• To compare the performance of ad hoc built low-cost sensor systems against certified, high-quality sensors.
• To analyze the impact of environmental factors and data processing on sensor accuracy.

Main Methods:

• Two independent low-cost sensor systems were deployed to measure various air quality parameters (PM, TVOC, CO2, formaldehyde), temperature, humidity, pressure, air flow, and GPS.
• Low-cost Particulate Matter (PM) sensors were calibrated against standard sensors used by the Emilia-Romagna region's air quality authority (ARPAE).
• Quantitative analysis focused on sensor performance, including time granularity, relative humidity effects, mass conversion from particle counts, and size detection.

Main Results:

• Low-cost sensors demonstrated good agreement with high-quality sensors for air temperature, relative humidity, and particle number concentration.
• Relative humidity significantly impacted sensor performance indicators.
• The study achieved good data quality and consistency among the tested sensors.

Conclusions:

• The proposed in-field comparison method, coupled with appropriate mass conversion techniques, effectively validates low-cost sensor data for automotive applications.
• Low-cost sensors show promise for widespread environmental monitoring, provided their performance, especially concerning humidity, is well-understood and accounted for.
• The findings support the reliable use of low-cost sensors for real-time air quality and energy parameter control in vehicles.