Singapore urged Indonesia on Monday to take "urgent measures" to tackle its forest fires as severe air pollution blown from Sumatra island choked the densely populated city-state.
Singapore's three-hour Pollutant Standards Index (PSI) climbed steadily throughout yesterday, crossing well past the officially designated 'unhealthy' threshold of 100 to reach a high of 155 by 10pm. It was the city-state's worst haze reading since 2006 when the PSI reached 226.
As at 10am on Tuesday, Singapore's PSI reading stands at 121.
Parts of neighbouring Malaysia were also suffering from the smoky haze, which is a recurring problem Southeast Asian governments have failed to solve despite repeated calls for action. The last reading for Malaysia at 7:00 am on Tuesday, however, showed some improvement with more areas moving back to the moderate range, only with parts of Johor and Terengganu still above the 100 mark.
The problem occurs in the dry season as a result of forest fires in the sprawling Indonesian archipelago, some of them deliberately started to clear land for cultivation.
The NEA said 138 "hotspots" indicating fires were detected on Sumatra on Sunday, and prevailing winds carried smoke over to Singapore. NEA had also alerted its Indonesian counterpart on the situation "and urged the Indonesian authorities to look into urgent measures to mitigate the trans-boundary haze occurrence".
People with heart and lung disease, those over 65 and children are advised by the NEA to "reduce prolonged or heavy outdoor exertion" even in "moderate" haze conditions, defined as a reading of 51-100.
Southeast Asia's haze problem hit its worst level in 1997-1998, causing widespread health problems and costing the regional economy billions of dollars as a result of business and air transport disruptions.
Click on to see more hazy photos from Singapore and Malaysia.