Relevance and Reliability of Outdoor SO2 Monitoring in Low-Income Countries Using Low-Cost Sensors

In the Western world, SO2 concentration in ambient air dropped to low levels, but some emission sources (e.g., merchant ships) and regions low-income countries) still emit substantial amounts of SO2. At those locations, monitoring is critical. However, countries do not have much access expensive reference instruments. Low-cost gas sensors might be an alternative, it unclear how reliable such measurements are. To evaluate performance low-cost same sensor has been subjected three different calibration methods: (1) performed tropical climate Cuba; (2) high-end Belgium; (3) a field at quality measuring station Belgium. The first two methods showed similar trends, suggesting that can calibrated with method. was hampered by concentrations. For campaign Cienfuegos, Cuba, method appeared sufficiently reliable. reliability increases increase concentration, so used Cuba instead