Marzuki Ismail

Indoor and Outdoor Relationships of Respirable Suspended Particulate Matter at Primary Schools in Kuala Terengganu, Malaysia

Studies have found that indoor air pollution affects human, especially children and the elderly, more compared to ambient atmospheric air. This study aims to investigate respirable suspended particulate matter (RSP) concentration in selected primary schools with different surrounding human activities, and to establish statistical relationships between indoor and outdoor air pollutant concentrations in each selected schools in Kuala Terengganu. Failure to identify and establish indoor air pollution status can increase health problems for these young students and degrade their learning environment and comfort. Indoor air quality (IAQ) parameters in seven primary schools were conducted during the monsoon season of August 2008 until March 2009. Ineach classroom, RSP, air velocity, relative humidity and temperature were monitored during school hours, and a complete walkthrough survey was completed. Results show a statistically significant difference for the six IAQ parameters between the seven schools at the 95% confidence level. Indoor concentration levels were mainly affected by RSP of outdoor concentration levels, since there are strong relationships of RSP concentration between indoor and outdoor in all schools except for control school. We conclude our findings by confirming the important influence of surrounding human activities on indoor concentrations of pollutants at primary schools in Kuala Terengganu.

Seasonal and long term variations of surface ozone concentrations in Malaysian Borneo

Malaysian Borneo has a lower population density and is an area known for its lush rainforests. However, changes in pollutant profiles are expected due to increasing urbanisation and commercial-industrial activities. This study aims to determine the variation of surface O3 concentration recorded at seven selected stations in Malaysian Borneo. Hourly surface O3 data covering the period 2002 to 2013, obtained from the Malaysian Department of Environment (DOE), were analysed using statistical methods. The results show that the concentrations of O3 recorded in Malaysian Borneo during the study period were below the maximum Malaysian Air Quality Standard of 100ppbv. The hourly average and maximum O3 concentrations of 31 and 92ppbv reported at Bintulu (S3) respectively were the highest among the O3 concentrations recorded at the sampling stations. Further investigation on O3 precursors show that sampling sites located near to local petrochemical industrial activities, such as Bintulu (S3) and Miri (S4), have higher NO2/NO ratios (between 3.21 and 5.67) compared to other stations. The normalised O3 values recorded at all stations were higher during the weekend compared to weekdays (unlike its precursors) which suggests the influence of O3 titration by NO during weekdays. The results also show that there are distinct seasonal variations in O3 across Borneo. High surface O3 concentrations were usually observed between August and September at all stations with the exception of station S7 on the east coast. Majority of the stations (except S1 and S6) have recorded increasing averaged maximum concentrations of surface O3 over the analysed years. Increasing trends of NO2 and decreasing trends of NO influence the yearly averaged maximum of O3 especially at S3. This study also shows that variations of meteorological factors such as wind speed and direction, humidity and temperature influence the concentration of surface O3.

Mapping the Spatial Distribution of Criteria Air Pollutants in Peninsular Malaysia Using Geographical Information System (GIS)

Air pollution is defined as the introduction by man, directly or indirectly, of substances into the air which results in harmful effects of such nature as to endanger human health, harm living resources and ecosystems, cause material damage, interfere with amenities and other legitimate uses of the environment (United Nations Environment Programme [UNEP], 1999). The air pollution sources is categorized according to form of emissions whether gaseous or particulates. Air pollution sources also can be distinguished by primary or secondary air pollutants. Primary air pollutants are in the atmosphere that exists in the same form as in source emissions, whereas, secondary air pollutants are pollutants formed in the atmosphere as a result of reactions such as hydrolysis, oxidation, and photochemical oxidation (David Liu & Liptak, 2000). World Health Organization (WHO) had been listed six “classic” air pollutants: carbon monoxide (CO), lead, nitrogen dioxide (NO2), suspended particulate matter (SPM) sulphur dioxide (SO2) and tropospheric ozone (O3) (World Health Organization [WHO], 1999).

The Weather and Climate of Tropical Tasik Kenyir, Terengganu

This study investigates the trend of weather and climate in Tasik Kenyir, Terengganu State based on seasonal monsoons utilizing nearest meteorological station of Kuala Terengganu. Data from 1985 to April 2016 was used to describe the physical environment of Kenyir Lake in terms of rainfall amount (mm), relative humidity (%), ambient temperature (°C), MSL pressure (hPa), and wind speed (m/s) and wind direction (degrees). The data was first divided by different monsoon seasons faced by Kuala Terengganu; Southwest Monsoon (SWM), Northeast Monsoon (NEM) and Inter Monsoon (IM). There exists significant different (p < 0.05) during these three monsoon seasons for rainfall amount, ambient temperature, and MSL pressure. Conversely, relative humidity shows no significant different between the monsoon seasons. Rainfall amount, relative humidity and MSL pressure noted high intensity during NEM with an increment of 250.1 mm, 0.3%, and 2.2 hPa from SWM and by 189.2 mm, 0.2%, and 1.3 hPa from IM, respectively. Meanwhile, there was a decrease of ambient temperature during NEM by 1.1 °C from SEM and 0.8 °C from IM. Prevailing wind direction was noticed from NE direction with mean value of 3.5 m/s. In conclusion, regardless of any monsoon seasons, there is no significant change in relative humidity variation, but rainfall amount, ambient temperature and MSL pressure shows significant change for each and every monsoon. The understanding of indigenous community on the changing of monsoon seasons might help them in early preparation for foods and other materials for their own survival and festive activities.

Effect of Zinc Coating Thickness on Corrosion Performance of Mild Steel in Atmospheric and Seawater Environment

The application of zinc coating as a protective film to the mild steel against corrosion attack in atmospheric and seawater environment was studied. The objective of this study is to evaluate the corrosion performance of mild steel coated by different thickness of zinc under salt spray and also immersion test. The corrosion measurement test was performed by weight loss and potentiodynamic polarization. From the experimental study, it was found that the corrosion rate of mild steel is inversely proportional to the zinc coating thickness. The result also showed that the corrosion rate of mild steel in the salt spray test is higher than the immersion test.

Effects of UV-HEPA Air Filters on Air Quality Status inside a Public Museum in Malaysia

Poor indoor air quality is a major threat towards workers since the office or office-like environment is now the workplace for the majority of the workforce in Malaysia. Workers in office buildings frequently have unexplained work-related symptoms or combinations of symptoms but evidence suggests that microbial contamination plays a part. Ultraviolet germicidal irradiation lights with high efficiency particulate air filter (UV-HEPA) are recognized for eradicating biological contaminants and capturing particles in indoor environments. Here, the effectiveness of UV-HEPA purification unit was obtained in two selected workplaces i.e. laboratory of conservation and laboratory of natural resources. Results show that there exist significance difference (P<0.05) on indoor air quality between pre-installation and post-installations of UV-HEPA filter in both selected room. Furthermore, it shows that UV-HEPA filter is effective in removing indoor air pollutants and improves the air quality. The use of UVGI lights with HEPA filter resulted in significant reduction in the concentration of microbes and respirable particulates within the ventilation systems. Keywords:indoorairquality,microbes,respirableparticulates,UV-HEPApurificationunit

Respirable Dust Exposure: Symptoms and Effect on Lung Function of Industrial Workers

Work environment factors such as air quality in the industry have become a public concern recently especially due to issues related to respirable dust. Most of industrial workers are exposed to dust during their daily work activities. A preliminary study was conducted at a paper based mill, palm oil mill and automotive plant in Malaysia to monitor the personal exposure of respirable dust. Personal sampling and questionnaires were administrated in purposed to determine the respiratory health symptoms and supported by a pulmonary lung function test. The result of the study showed most of the workers in paper based mill were exposed to respirable dust when the Time Weightage Average (TWA) result was above the permissible exposure limit which is 5 mg/m3 and 3 mg/m3 from Occupational Safety and Health Administration (OSHA) and American Conference of Governmental Industrial Hygienists (ACGIH) standard respectively. From the survey feedbacks, out of 30 symptoms, there are only five symptoms that are significant with the year of exposure. For pulmonary lung function test, there were 81.81% workers are in normal of spiro status for paper based mill. Meanwhile, for palm oil mill and automotive plant, there were almost 53.33% and 65.63% workers in normal spiro status respectively. However, there was no significant relation with the variables noted. Therefore, for a better future for industrial workers, some engineering control and approach have been suggested to the safety and health team to control machines that are fully operated and consider looking into the dust concentration.