1. Air quality is driven mainly by two factors in Sri Lanka a. The level of emissions from various source points. For example, the more fossil fuels are burned for transport or energy, the more emissions in the air. To improve air quality, we need to target source points and present alternative policy solutions, which are already available but not effectively implemented.
b. The shift in the monsoon. The public is provided a reprieve from otherwise high levels of air pollution thanks to monsoon conditions. This is clearly demonstrated in Exhibit 2, where a significant improvement in Colombo’s air quality is seen between April/May and September/October each year. As such, the monsoon does help mask the air pollution problem.
2. What does the public need to know when interpreting air quality data
a. The Air Quality Index (AQI) measured in µg/m³ translates into a (colour-coded) health index, signifying the potential adverse impact to an individual’s health (see Exhibit 1).
b. The safeguard measures are relatively simple behavioural changes such as avoiding outdoor activity, closing the windows, and wearing an approved mask e.g.N95. Additional measures can be taken in situations where air quality is in the unhealthy category or worse for prolonged periods. For example, in the United States, measures such as setting aside a room in the home with an air purifier is recommended during the bushfire season, so that occupants may retreat into the safe space until air quality improves.
Disclaimer: Readings of some sensors are not updated due to prevailing situation (power outages and economic constraints) in Sri Lanka.