Singapore records unhealthy air quality in central, eastern and western regions

Air quality in the Republic deteriorated further on Monday (Sept 14) afternoon, with the eastern and western regions joining central Singapore in recording unhealthy 24-hour Pollutant Standard Index (PSI) readings.

At 4pm, 24-hour PSI reading was between 87 and 115, in the moderate to unhealthy range, with unhealthy readings in the central (115), eastern (101) and western (101) regions.

Meanwhile, 1-hour PM2.5 hit a recent high of 132 in central Singapore at 2pm, before easing to 128 at 4pm.

In other parts of Singapore, the one-hour PM2.5 reading at 4pm was between 64 and 89, in the elevated range.

PM2.5 indicates the level of fine micro-pollutants in the air and is the current air quality that matters — when planning to conduct or participate in outdoor activities immediately.

Readings of between 51 to 100 are in the moderate-band, while readings of between 151 and 250 denote the high-band.

The highest one-hour PM2.5 concentration ever recorded in Singapore was 471 µg/m³ in western Singapore at 11pm on October 19, 2015.

What the PM2.5 reading means for outdoor activities

When PM2.5 readings are in the elevated band, members of the public should reduce strenuous outdoor activity for the next hour.

Vulnerable persons such as the elderly, pregnant women, children, and persons with chronic lung or heart disease should avoid strenuous outdoor activity.

However, if readings hit the high-band, all healthy persons should avoid strenuous outdoor activity for the next hour, while vulnerable persons should avoid all outdoor activity.

Members of the public should note that the health impact of haze is dependent on one's health status, the PSI level, and the length and intensity of outdoor activity.

For the general population, symptoms that may arise from short-term exposure include throat or eye irritations.

These symptoms are expected to resolve once a person withdraws from the exposure.

周一（9 月 14 日）下午，新加坡的空气质量进一步恶化，东部和西部地区与新加坡中部地区一样，记录到 24 小时污染物标准指数 (PSI) 读数不健康。

下午 4 点，24 小时 PSI 读数在 87 到 115 之间，处于中度至不健康范围内，中部 (115)、东部 (101) 和西部 (101) 地区的读数为不健康。

与此同时，新加坡中部地区 1 小时 PM2.5 浓度在下午 2 点达到近期最高值 132，随后在下午 4 点回落至 128。

在新加坡其他地区，下午 4 点的 PM2.5 一小时读数在 64 到 89 之间，处于较高水平。

PM2.5 表示空气中细小污染物的含量，是当前空气质量的重要指标——尤其是在计划立即进行或参与户外活动时。

读数在 51 到 100 之间属于中等范围，而读数在 151 到 250 之间则属于高范围。

新加坡有记录以来最高的 PM2.5 一小时浓度为 471 µg/m³，出现在新加坡西部，时间是 2015 年 10 月 19 日晚上 11 点。

PM2.5读数对户外活动意味着什么

当 PM2.5 读数处于较高水平时，公众应在接下来的一个小时内减少剧烈的户外活动。

老年人、孕妇、儿童以及患有慢性肺病或心脏病等弱势群体应避免剧烈的户外活动。

但是，如果读数达到高值，所有健康的人在接下来的一个小时内都应该避免剧烈的户外活动，而易感人群应该避免所有户外活动。

公众应注意，雾霾对健康的影响取决于个人的健康状况、PSI 值以及户外活动的持续时间和强度。

对于普通人群而言，短期接触可能出现的症状包括喉咙或眼睛刺激。

一旦停止接触这些物质，这些症状预计会消失。