<p>Ten years of continuous monitoring data (2000-2010) from the Air Quality Division, at the Malaysian Department of Environment are used to investigate the relationships between ambient levels of ozone (O3), nitric oxide (NO) and nitrogen dioxide (NO2) as a function of NOx, in Kemaman, Malaysia, wherewith the dominant sources of ozone precursors are industrial activities and road traffic.</p>
<p>In addition, variation of oxidant OX (O3 and NO2) concentration with NOx was also examined. The analyses established a weak linear relationship between O3 and NOx, signifying that Kemaman area is not NOx sensitive but possibly VOC-sensitive area. The level of [OX] is influenced byNOx-independent and NOx-dependent contributions.</p>
<p>The former is due to regional background O3 concentration while the latter correlates to the local level of primary pollution. The measured concentrations of the pollutants varied as a function of time.</p>
<p>The analyses also show that the diurnal cycle of ground level ozone concentration has a mid-day peak while lower concentration occurs at night time.</p>
<p>[author abstract]</p>