2005 Malaysian haze

Haze is caused by "hotspots" (zones with high temperature levels as seen via satellite imagery) in Malaysia and Indonesia. Lingering smoke from forest fires on the Indonesian island of Sumatra are identified as the primary cause. Farmers regularly burn scrub and forest to clear land during the dry season for agricultural purposes, but this had been the worst haze to hit Malaysia since the 1997 haze.

On 10 August 2005, air quality in the Malaysian capital city of Kuala Lumpur was so poor that health officials advised citizens to stay at home with doors closed. Some schools were closed to keep children from being exposed to the haze.

On 11 August 2005 a state of emergency was announced for the world's 12th largest port, Port Klang and the district of Kuala Selangor after air pollution there reached dangerous levels (defined as a value greater than 500 on the Air Pollution Index or API). This was the first time the state of emergency had been imposed in Malaysia since the September 1997 haze, when Sarawak was placed in a state of emergency due to similar reasons.

The state of emergency in the two affected areas meant that schools, government officials, the port, and offices were closed. Shops carrying necessities, however, such as supermarkets and pharmacies remained open.

After the API levels dropped to acceptable levels, the state of emergency was lifted on 13 August.

By 13 August 2005, air quality and visibility returned to normal in Kuala Lumpur, as the haze moved northwards to the states of Perlis, Kedah and Penang, according to the Department of Environment (JAS) API reading. On 16 August, air quality throughout Malaysia had returned to normal according to JAS statistics, as the haze was blown further northwards into Thailand.

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Wikipedia