SCHOOLS were ordered to close and residents urged to stay home yesterday, as Dumai's pollutants standard index (PSI) soared to a hazardous 776.
Visibility dropped to 50m, prompting port authorities to issue warnings to ships, as the dry weather and open burning took its toll on the city in Sumatra.
"The priority for ship captains, operators and shipping agents should be on safety; they should not force themselves to sail in such conditions," Dumai port's head of safety, Captain Ivan Apriano Polin, told reporters.
Flights to and from the provincial capital of Pekanbaru were also delayed by several hours.
The return of the annual haze so early this year has angered residents, who questioned the government's ability to tackle the problem of forest and plantation fires.
Riau disaster mitigation agency head Said Saqlul Amri also hit out at a procedural snag. He said firemen cannot tap the 10 billion rupiah (S$1.1 million) worth of emergency funds from provincial coffers because only four districts and cities have declared a state of emergency, short of the seven needed to use the money.
Dumai, about 270km north- west of Singapore, was at the epicentre of the worst haze ever last June when the PSI crossed 900 and air pollution in Singapore and Malaysia hit record highs.
Singapore's National Environment Agency said about 20 hot spots were detected in Sumatra yesterday, and the PSI for Singapore was within the good range.
Dr Winston Chow of the National University of Singapore's geography department said the smell of the haze can be present in the evenings and early mornings, when there is less movement in the air.
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