The rain did not seem to reduce the haze. The bushfires along Lumut-by-pass road did not seem to be in a hurry to end. The wind was blowing towards my workplace, so eventually the area got covered by haze. It was quite bad; I could smell smoke in the office. Luckily we had one of those industrial air purifiers, which I put in the middle of my office. It was slightly noisy; but I knew I would choose noise over polluted air anytime.
At the lab, we have one of those machine that monitors air quality. We had started the air quality monitoring since early last week. It seemed like the haze got worse in the evening. It was probably caused by the land breeze that blew the haze towards the plant. On Monday evening, there was a period of three hours in the middle of the evening when the PSI (pollution standard index) exceeded 200. According to the Brunei's Department of Environment, Park and Recreation, PSI of over 200 is considered to be very unhealthy and the wearing of dustmasks is recommended. Fortunately, the PSI reading during the day is below 100, which is considered as good or moderate.
However, please take the PSI reading with a pinch of salt. The PSI reading differs significantly from places to places, as it depends on the air quality at that particular place. I am not sure how many air monitoring equipment the government has, but I recall hearing there are those equipment at the Brunei International Airport and the KB Weather Station near the Pandan Mosque. There is one each at the BSP Lab and the BLNG Lab. Therefore, if you spot bushfire in, say, Muara and the haze is contained within that area, the air quality reading that you see might not tell you the whole picture about the air quality in the whole of Brunei as the equipment is in the Berakas area.
Also, the PSI being reported is normally the 24-hour average. The haze could be very bad in the evening, reaching PSI of over 200, but it could clear up during the day with PSI of below 100. Therefore the average PSI over 24-hour period may be sub-100. It would be good to see the hourly average as it can tell you an almost up-to-date PSI reading.
The haze outbreak that we are facing at the moment is considered to be localised haze, meaning that the haze that the residents in Lumut see is caused by bushfires in the Lumut area and may not be felt by the residents of Seria. The haze episode that Brunei experienced in 1997-1998 was caused by regional haze as it was caused by forest fires in almost all parts of Borneo, which blanketed the South-east Asian region.