Emission policies and clean fuel go hand in hand.
Cut vehicle emissions by more than half.
Key result
The change
Moving from Euro 3 to Euro 5 standards
The result
Cut vehicle emissions by more than half.
In 2000, Bangkok was one of the top ten most polluted cities in Asia, with a vehicle population of five million.
Standards alone did not do it
Many studies have shown that emissions standards alone do not achieve the benefits of clean air quality. Rather, improved fuel is key. With stricter emission standards today, we are seeing a rise in the demand for clean fuel components for improving fuel quality.
What changed
Switching from Euro 3 to Euro 5 has reduced Thai emissions by more than half.
What was measured
Roadside PM2.5 in Bangkok fell on every measure between 2011 and 2017. A linear regression across the period returns R² = 0.7778.
- Maximum: 112 → 77 µg/m³
- 95th percentile: 72 → 52 µg/m³
- Average: 35 → 26 µg/m³
- Minimum: 9 → 8 µg/m³
Figures transcribed from the chart on ACFA's current case study page. Endpoint values should be checked against Dr Supat Wangwongwatana's presentation before publication; the intermediate years have not been transcribed.
Presentation of Dr Supat Wangwongwatana
Further reading