Three main tipping areas within
the landfill site were identified as main odour emission sources and odour gas samples were
collected during a dumping operation period by using an odour sampling system, which
includes a battery-operated air pump, a sampling vessel, and nalophaneNATM odour bags.
About 60 L of foul gas was collected for each of odour samples. A wind tunnel was also
employed in this sampling work and the collected odour samples were analyzed by an
olfactometer (Olfactomat-n1) which follows a new European Standard Method (EN13725) to
determine odour concentration. Three odour samples collected from the three tipping areas of
the landfill site were transported to our odour research laboratory and analyzed by the
olfactometry method on the same day, in which 6 qualified panellists participated in the odour
testing session, who were previously selected through screening tests by using a 50 ppm of
certified n-butanol gas as a standard odour material. The results of odour concentrations are
shown in Table 1.