4. CONCLUSION
Concentrations of 24-hour average PM10 at primary and high schools, Lak Muang
Connection, Nakhon Si Thammarat were rather high when compared to NAAQS of Thailand
and were exceeded WHO air quality guidelines. Levels of average PM10 during semester were significantly higher than that during the semester break: 27 μg/m3 and 18 μg/m3 increase at primary and high schools, respectively. Appropriate traffic management could be
implemented to prevent from both short- and long- term health impacts. Future works should
be included more PM data collection to obtain the robust information. Mathematic models
could be also applied to test the validity of traffic management scenarios on air quality
impacts and to confirm its contribution to the local air quality
ACKNOWLEDGMENT
The authors would like to express appreciation to the Institute of Research and Development,
Walailak University for the financial support. Extended thanks go to the Pollution Control
Department (PCD) for monthly average PM10 data of Thailand in 2013