Association between walkability index and pedestrians’ perspective in reducing exposure of schoolchildren to ground level ozone / Nazatul Syadia Zainordin
Ozon paras tanah (O3) adalah satu pencemar gas yang mana memberi kesan ketara kepada kesihatan manusia dan alam sekitar. Pendedahan kepada pencemar ini dan prapenandanya adalah lebih bahaya kepada kanak-kanak jika dibandingkan dengan orang dewasa. Prapenanda O3 kebanyakkannya dikeluarkan daripada ekzos kenderaan. Perjalanan tidak bermotor telah menjadi pilihan dalam menyelesaikan masalah ini. Oleh itu, kajian ini tertumpu kepada kanak-kanak sekolah dan tujuannya adalah untuk menilai adanya kemudahan dan keadaan sedia ada kemudahan pejalan kaki dengan membangunkan indeks kebolehlaluan. Sudut pandang dan sikap pejalan kaki juga diambil kira untuk mendapatkan persepsi terhadap kemudahan pejalan kaki yang telah disediakan dan sikap mereka dalam mengubah mod sedia ada kepada berjalan kaki. Kepekatan O3 ambien dan prapenandanya juga diselidik untuk melihat tahap pendedahan semasa bagi pencemar-pencemar ini terhadap kanak-kanak sekolah. Berdasarkan indeks kebolehlaluan bagi semua 22 buah sekolah terpilih, SPP merekodkan indeks tertinggi sementara SPC, SBJ, SSA, dan STK merekodkan indeks terendah. Perhatian yang lebih telah diberikan terhadap reka bentuk geometri kemudahan pejalan kaki di kawasan bandar jika dibandingkan dengan kawasan pinggir bandar dan luar bandar disebabkan jumlah trafik yang tinggi. Daripada analisa satu-hala ANOVA dan t-test bebas, skor responden terhadap elemen kemudahan laluan pejalan kaki dan tahap persetujuan dengan masalah persekitaran, kesedaran dan potensi dalam mengubah mod sedia ada kepada berjalan kaki adalah berkaitan dengan jenis responden, bangsa dan jantina. Walau bagaimanapun, faktor jarak perjalanan tidak mempengaruhi skor dan tahap persetujuan responden. Semasa menilai kepekatan ambien, kebanyakan pencemar-pencemar terutamanya prapenanda O3 adalah lebih tinggi di SST disebabkan sumber antropogenik berdekatan kawasan tersebut manakala kepekatan O3 adalah lebih tinggi di SSH (32.48 ± 15.97 ppb). Akhirnya, model FFBP telah dibangunkan dan ia menunjukkan bahawa SSN mempunyai model FFBP terbaik dengan ukuran ketepatan yang paling tinggi dan ukuran ralat yang rendah. Kesimpulannya, indeks kebolehlaluan yang lebih tinggi dijangkakan dalam meningkatkan kesanggupan kanak-kanak sekolah untuk berjalan kaki ke sekolah tanpa mengambil kira jarak perjalanan dari rumah ke sekolah. Reka bentuk geometri kemudahan laluan pejalan kaki dan ukuran keselamatan berdekatan sekolah didapati menjadi isu yang sangat penting yang perlu dilihat dalam menggalakkan mereka mengubah mod sedia ada kepada berjalan kaki. Justeru, ia dapat mengurangkan pendedahan O3 dan prapenandanya terhadap kanak-kanak sekolah. Bagi pembangunan alat ramalan yang baru untuk mengukur kepekatan di masa hadapan berhampiran empat kawasan sekolah diharap dapat membantu pihak berkuasa tempatan bagi memantau dan meramal pendedahan kepada kepekatan O3 terhadap kanak-kanak sekolah dengan adanya parameter-parameter bebas. __________________________________________________________________________________
Ground level ozone (O3) is one of the gaseous pollutants that significantly affects human health and environment. Exposure to this pollutant and its precursors is more severe to children than adult due to lower breathing height. O3 precursors are mainly emitted from vehicle exhausts. Non-motorized travel has become an option in solving these problems. Therefore, this research is focus on school children and the aims are to assess availability and current condition of the facilities by developing the walkability index. Pedestrians’ perspectives and attitudes were also considered to gain their perceptions on provided pedestrian facilities and their attitudes in changing current mode to walking. Ambient O3 concentrations and its precursors were also investigated to observe the current level of exposure of these pollutants to school children. Based on the walkability index for all 22 selected schools, SPP recorded the highest index which is nine while SPC, SBJ, SSA, and STK recorded the lowest which are one. Much attention has been given in terms of geometric designs of pedestrian facilities in urban area compared to sub-urban and rural area due to high traffic volume. From the analysis of one-way ANOVA and independent t-test, respondents’ score on the elements of the pedestrian facilities and level of agreement with environmental problems, awareness and potential in changing the current mode to walking were related to types of respondents, race and gender. Nevertheless, factor of travel distance did not influence the given score and level of agreement by respondents. While assessing the ambient concentrations, most pollutants mainly O3 precursors were much higher at SST due to more anthropogenic sources nearby the area when O3 concentrations were higher at SSH (32.48 ± 15.97 ppb). Lastly, FFBP models were developed and it is found that SSN has the best FFBP models with the highest accuracy measures and lower error measures. In conclusion, higher walkability index is expected to increase the willingness amongst school children to walk to school regardless of the travel distance from home to school. Geometric design of pedestrian facilities and safety measures nearby schools area were found to be the most important issues to look through in order to encourage them to change current mode to walking. This change could reduce the exposure of schoolchildren to O3, and its precursors. As for development of a new predictive tool for future concentrations nearby four schools area may help local authorities to observe and predict the exposure of O3 concentrations on school children with the availability of independent parameters.
Association between walkability index and pedestrians’ perspective in reducing exposure of schoolchildren to ground level ozone / Nazatul Syadia Zainordin
Association between walkability index and pedestrians perspective in reducing exposure of school children to ground level ozone_Nazatul Syadia Zainordin_A9_2017_MYMY