3-hour PSI tops 100 in Singapore, dips into 'Unhealthy' range

Today Online 20 Mar 15;

SINGAPORE: Haze was reported by members of the public on Friday afternoon (Mar 20), with the three-hour Pollutant Standards Index (PSI) reading hitting 102 at 4pm, dipping into the 'Unhealthy' range.

The three-hour PSI reading at 8am was 65, before steadily rising. It continued to increase throughout the day. At 2pm, the 24-hour PSI was 64 to 73.

It crossed into the 'Unhealthy' range at 102 at 4pm and by 6pm, it peaked at 106. At 8pm the 3-hour PSI dropped back in the 'Moderate' range, at 99.

The Meteorological Service Singapore (MSS) said that the "slight haziness could be due to the accumulation of particulate matter in the air under light wind conditions".

The National Environment Agency (NEA) added that "burning activities in the Northern ASEAN region, Peninsular Malaysia and Sumatra could have contributed to the increased concentration of particulate matter."

NEA said hazy conditions are expected to persist for the rest of the day, with Saturday's 24-hour PSI expected to be in the 'Moderate' range. It said "given the air quality forecast for the next 24 hours, everyone can continue with normal activities".

At 12.40pm, Channel NewsAsia received a call from Mr Wee, a member of the public, who said it was “very hazy” in Macpherson. A Twitter user, Jonathan Leong, said that it was "slightly hazy in Jurong this morning."

Yudi Setiawan also posted a photo on Instagram of hazy conditions this morning.

- CNA/ct


Air quality hits unhealthy levels, PSI peaks at 106
Today Online 21 Mar 15;

SINGAPORE — Air quality reached unhealthy levels yesterday, when the three-hour Pollutant Standards Index (PSI) breached the 100-mark. And the hazy conditions could continue into today, with the 24-hour PSI to be in the moderate range of 51 to 100.

Yesterday, the three-hour PSI crossed into unhealthy territory at 4pm, and peaked at 6pm at 106, before dipping out of the unhealthy range at 8pm. By 9pm, the three-hour PSI reading was 88. The 24-hour PSI readings ranged between 75 to 83.

Responding to media queries, the National Environment Agency (NEA) said: “The haziness is likely due to an accumulation of increased particulate matter in the atmosphere under light wind conditions throughout today. Burning activities in the northern ASEAN region, peninsular Malaysia and Sumatra could have contributed to the increased concentration of particulate matter.” The regional haze map posted on its website showed that clusters of hot spots were detected mainly in Myanmar and some were scattered in Thailand.

Air quality enters the unhealthy level when PSI is between 101 and 200. The three-hour PSI readings began climbing after 7am yesterday, reaching 71 at 11am, 74 at noon and 80 at 1pm. It then hit 86 at 2pm and 94 at 3pm.

The agency added that PM2.5 levels were elevated in most regions of Singapore yesterday. Noting that prevailing winds today are expected to be light and variable in direction, they said hazy conditions can still be expected.

Given the air quality forecast for the next 24 hours, the public can continue with normal activities, the NEA said, but noted that the health impact of haze is dependent on one’s health status, the PSI level and the length and intensity of outdoor activity.

Haze returns, expected to continue today
Feng Zengkun The Straits Times AsiaOne 21 Mar 15;
Hazy skies returned to Singapore yesterday and are expected to darken part of the island today as well.

The National Environment Agency (NEA) said last night that the return of the haze was likely due to an accumulation of increased particulate matter in the atmosphere under the light wind conditions. "Burning activities in the northern ASEAN region, Peninsular Malaysia and Sumatra could have contributed to the increased concentration of particulate matter," it added.

The day began yesterday with relatively clear skies, but the air quality deteriorated throughout most of the day, from 1am to 6pm, before improving slightly in the night.

By 4pm, the three-hour Pollutant Standards Index (PSI) had crossed 100, the threshold where air becomes unhealthy. The three-hour PSI averages air quality readings in the previous three hours.

By 5pm, even the 24-hour index, which the Government has said is a better indicator of whether people should worry about their health, had inched close to that threshold, ranging from 69 to 92 across the island.

People in eastern Singapore, where the haze was worst yesterday evening, said they were worried that the burning smell was here to stay. "I was really hoping we wouldn't have to go through the face masks and air purifiers again," said 28-year-old sales assistant Joy Thng.

The NEA said hazy conditions can still be expected today, although the 24-hour PSI is expected to be in the moderate range.

Everyone can continue with normal activities given the air quality forecast, but people who are not feeling well should seek medical attention, it said.