Published on: 8 September 2026, 3:02PM

Singapore haze: What PSI and PM2.5 readings really mean for your health

Prof Rajasekhar Balasubramanian discusses what it means when Singapore’s PSI enters the unhealthy range and whether air purifiers can offer effective protection indoors.

Prof Rajasekhar Balasubramanian(opens in new tab), from the Department of Civil and Environmental Engineering(opens in new tab), shared that PSI and PM2.5 readings help indicate the concentration of fine particles in the air that can enter the lungs, with vulnerable groups needing to be especially cautious about outdoor activities. He also noted that while N95 masks can help filter small particles, air purifiers are only effective if chosen appropriately, such as by checking their Clean Air Delivery Rate (CADR) rating and maintaining filters regularly.

(CNA 938, 8 September 2026)(opens in new tab)

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