Schools reacted quickly. Physical‑education lessons were cancelled, outdoor activities discouraged and assemblies moved inside classrooms. Parents reported that students were told to stay away from fields and to wear masks. Mr Arul Kumar, who collected his son from First Toa Payoh Primary, said teachers asked pupils to stay indoors and stay hydrated. Geraldine Goh, a parent at Convent of the Holy Infant Jesus (Primary), said her daughter now wears a mask every day and that the school holds recess inside.

A clean‑up project at Jurong Central Park was also trimmed. What was meant to be a two‑hour activity for about 100 Institute of Technical Education students was reduced to 45 minutes after the organisers checked the PSI and followed safety guidelines.

Even regular exercisers felt the change. Mr Lim, a retiree who jogs twice a day, said he now splits his usual 5 km run into shorter segments, resting after each kilometre, because the haze makes long runs uncomfortable.

The haze sparked a surge in protective purchases. Madam Tan, 73, bought a new box of surgical masks after the ones she kept from the COVID‑19 pandemic expired. “I felt my eyes tearing, so I bought some,” she explained. Meanwhile, 68‑year‑old Peter Wang visited Best Denki looking for an air purifier equipped with a high‑efficiency particulate air (HEPA) filter, saying the rising PSI makes him nervous.

Some families still go about their day unchanged. Ms Pearlie Toh, waiting outside Nan Hua Primary School, said her Primary‑3 son has not shown any breathing problems and she will only use a mask if the haze gets worse.

The Formula 1 Singapore Grand Prix continued as scheduled. Organisers said there are no current plans to alter the race or its entertainment programmes, but the Singapore Tourism Board confirmed it has contingency plans that trigger according to specific PSI and 1‑hour PM2.5 thresholds.