18 – 24 Oct 2021

Colombo Bayleaf Station recorded the highest AQ values last week, while the rest of the Colombo based stations (USEM and Overseas School), Gampaha and Ratnapura recorded values above acceptable levels. The Central province based AQ stations: Akurana and Dambulla were the only stations to record AQ levels within the acceptable range last week.

An analysis of weekly monitored air quality of some of the most urbanized and industrialized cities in Sri Lanka and a guide to air quality for beginners are presented herewith.

Highlights

Weekly Air Quality in Selected Towns of Sri Lanka
  • Akurana : AQ was considered satisfactory and air pollution posed little risk.
  • Colombo (Bayleaf): AQ was a little more polluted than in other stations.
  • Colombo (Overseas schools) : AQ was considered satisfactory and air pollution posed little risk.
  • Colombo (USEM) :  AQ was considered satisfactory and air pollution posed little risk.
  • Dambulla :  AQ was considered satisfactory and air pollution posed little risk.
  • Digana : No Updates.
  • Gampaha: AQ was considered satisfactory and air pollution posed little risk.
  • Kalawana: No Updates.
  • Kandy : No Updates.
  • Kurunegala : No Updates.
  • Nachchaduwa : No Updates.
  • Nawalapitiya : No Updates.
  • Norochcholai : No Updates.
  • Rathnapura : AQ was considered satisfactory and air pollution posed little risk.
MONITORING

The table below summarizes the weekly average AQI and the highest daily peak obtained during the week for each station.

AIR QUALITY BASICS

Air pollution, a widely- talked and argued topic today has been a primary cause of unforeseen climatic changes, many health problems associated with respiratory diseases and ecosystem damage. Vehicular and industrial emissions, dust, burning of fossil fuels, open burning of garbage waste and natural phenomena such as volcanoes, wildfires and pollen contribute to air pollution. Polluted air consists of both particulate matter of fine dimensions and gaseous matter. The presence of these impurities decreases the pureness of the air we breathe.

AQI

United States Environmental Protection Agency (US EPA) has set up a standard to measure the level of air pollution by the following 5 major air pollutants:

  • Ground- level ozone (O3)
  • Particle pollution (PM2.5 and PM10)
  • Carbon monoxide (CO)
  • Sulphur dioxide (SO2)
  • Nitrogen dioxide (NO2)

Particulate matter of diameter less than 2.5 micrometers (PM2.5) and diameter less than 10 micrometers (PM10) and gases, ozone, carbon monoxide, sulphur dioxide and nitrogen dioxide have been identified as major air pollutants.

The AQI standard for ozone and particle pollution according to US EPA comprises of six categories. Each category is assigned a specific colour and corresponds to a different level of health concern. As the scale grows the air quality turns from good to extremely unhealthy.

Weekly Air Quality in Selected Towns of Sri Lanka

OUR MONITORING

At FECT we have air quality measuring devices stationed at the following locations:

  • Akurana
  • Colombo US Embassy
  • Bayleaf Restaurant- Colombo
  • Digana
  • Kurunegala
  • Nachchaduwa
  • Nawalapitiya
  • Norochcholai

Access to real- time air quality data from laser air quality sensoring instruments operated by FECT is available at www.cleanair.lk