Morphology Analysis of Fine Particles in Background Station of Malaysia

A study have been conducted at Jerantut, Pahang. PM2.5 concentrations were collected continously for 14 days and were analyzed to investigate time series and diurnal variations. Range of PM2.5 concentration was between 6.0ug/m3 and 98ug/m3 with average 30.43 ± 15.07ug/m3. The mean temperature was 28.61°C, while relative humidity and wind speed were 76.49% and 0.56m/s. From hourly variations, the percentage of PM2.5 concentration that exceed USEPA and WHO standards are 30.36% and 56.85%, respectively. Due to rush hour, diurnal pattern shows that PM2.5 concentration had the first peak between 6.00 to 9.00 h, the second peak between 12.00 to 13.00 h and the third peak between 19.00 to 21.00 h. PM2.5 shows a weak negative linear relationship with wind speed and temperature but shows a weak positive linear relationship with relative humidity. Morphology characteristic provides information about particle sources, atmospheric history, formation, reactivity, transport and removal of atmospheric chemical species. From FESEM analysis, the particles were categorized into two groups that are biological particles and anthropogenic particles. The biological particles such as fungal spore, brochosome and fungal hyphae were recognised from their morphology characteristics while anthropogenic particles such as soot were recognised from their morphology characteristics and weight percentage of elemental components

Characterization of Chemical Composition in Fine Particles (PM2.5) from Industrial Site in Malaysia

This research aims to investigate variations of fine Particulate Matter (PM2.5) and chemical composition in an industrialized area. Concentration levels of fine Particulate Matter (PM2.5) were continuously monitored at three sampling site S1, S2 and S3. The variations of PM2.5 concentration were analysed using descriptive statistics, time series plot, diurnal plot and correlation. Source apportionment and factor analysis were carried out using the chemical composition data from ICP-OES. Meteorological effects on PM2.5 concentration were used to investigate the effects on PM2.5 concentration. The results showed that, the average PM2.5 concentration was 19.75 ± 12, 46.68 ± 27, and 20.55 ± 9 ?g m-3 at sites in a S1, S2 and S3, respectively. The highest PM2.5 concentration was recorded in S2 (115 ?g m-3). The PM2.5 concentration in the diurnal plot exhibited an inversed unimodal pattern during morning (7:00 to 9:00) and evening (16:00 to 18:00). PM2.5 concentration in S2 on weekends was 36% lower than that on weekdays. PM2.5 was found to exhibit an inversed relation with wind speed and temperature. Although wind speed had a negative association with PM2.5 in S1 and S2, a positive correlation was observed at S3. Source apportionment from factor analysis distinguished three groups of possible sources; crustal materials (Al, K, Sr, Ti and Na), vehicles emission (Cr, Fe, Mn, Zn and Ni) and industrial activities (Ca, Mg and Pb)

Transformational characteristics of ground-level ozone during high particulate events in urban area of Malaysia

Observations of ground-level ozone (O3), nitric oxide (NO), nitrogen dioxide (NO2), particulate matter (PM10) and meteorological parameter (temperature, relative humidity and wind speed) fluctuations during high particulate event (HPE) and non-HPE in Malaysia have been conducted for 2 years (2013 and 2014). The study focuses on urban areas, namely, Shah Alam, Petaling Jaya and Bandaraya Melaka. The diurnal variations of ground-level O3 concentration were higher during HPE than those during non-HPE in all urban areas. The concentration of O3 fluctuated more in 2014 than 2013 due to the higher incidences of HPE. Temperature and wind speed fluctuated with higher PM10, NO2 and NO concentrations during HPE than those during non-HPE in all urban sites. Relative humidity was lower during HPE than that during non-HPE. Positive correlations were found between PM10 and ozone during HPE for Shah Alam and Petaling Jaya with 0.81 and 0.79, respectively. Meanwhile, negative correlation (− 0.76) was recorded for Bandaraya Melaka. The non-HPE correlation of PM10 and O3 showed negative values for all locations except Petaling Jaya (0.02). Temperature and wind speed shows a strong positive correlation with ozone for all locations during HPE and non-HPE with the highest at Shah Alam (0.97). Inverse relationships were found between relative humidity and O3, in which the highest was for Shah Alam (− 0.96) in 2013 and Shah Alam (− 0.97) and Bandaraya Melaka (− 0.97) in 2014. The result of the ozone best-fit equation obtained an R2 of 0.6730. The study parameters had a significant positive relationship with the ozone predictions during HPE

Dependency of biological contaminants on temperature and relative humidity within praying halls of mosques

The widespread use of Air Conditioning Split Units (ACSU) to cool the air inside mosques may pose potential adverse health effects, secondary to exposure to biological contaminants. To address this issue, the dependencies of biological contaminants (bacteria and fungi) on temperature (T) and relative humidity (RH) of the ‘mosques’ indoor air were evaluated. A total of 25 mosques were investigated during the periods in which their respective congregators were performing Zohor or Friday, and Asar prayers. The recorded average indoor bacteria and fungi concentrations were 382.6±143.9 cfu/m3 and 229.4±165.5 cfu/m3, respectively. However, the study found that masses of bacteria aerosol within the indoors of certain mosques (10 out of 17 ACSU mosques and 1 out of 8 non-ACSU mosques) exceeded the limit recommended by Malaysian standard for indoor air quality (500 cfu/m3). Meanwhile, the results of regression analyses suggested that T and RH of the indoor air have high influence on airborne bacteria and fungi. The variations in bacteria concentrations due to the influence of T and RH in ACSU mosques (T= 92.3%; RH= 90.3%) were higher than in non-ACSU mosques (T= 82.75%; RH= 81.7%) whereas the variations in fungi concentrations in non-ACSU mosques (T=70.45%; RH= 71.45%) were higher than in ACSU mosques (T= 66.05%; RH= 60.7%). This research shows that the growth of bacteria and fungi within the prayer halls of mosques in Malaysia is very much dependent on its indoor T and RH

Developing criteria for evaluations of water closet facilities in Malaysian mosques and it’s compliance with standards, guidelines and legislation

Water closets generally provide general facilities, such as wash-hand basins, ablution areas, shower areas and water cubicles (including those for the disabled). This study seeks to developed a list of criteria for evaluation of the design of these ancillary components as defined in various Malaysian standards and guidelines relevant to water closet design, namely, Malaysian Standard MS 2577: 2014 (Architecture and Asset Management of Masjid – Code of Practice), Malaysian Standard MS 2015: Part 1: 2006 (Public Toilet – Part 1: Minimum Design Criteria), Malaysian Standard MS 1184: 2014 (Universal Design and Accessibility in the Built Environment – Code of Practice, Second Revision), JKR 1999 (Guidelines on Buildings Requirements for Disabled Persons) and UBBL: 1984 (Unit Building By-Laws – Part III: Space, Light and Ventilation). A five-point rating scale was developed for the access audit (1=not provided; 2=provided but below the recommendation; 3=provided and exactly as the recommendation; 4=provided but above the recommendation; 5=provided but not in the recommendation). The scores of every criterion were computed to determine the compliance percentage. The study was conducted in five mosques to assess the on-site and as-built compliance of their water closets

Time effects of high particulate events on the critical conversion point of ground-level ozone

Particulate matter (PM), especially those with an aerodynamic particle size of less than 10 μm (PM10), is typically emitted from transboundary forest fires. A large-scale forest fire may contribute to a haze condition known as a high particulate event (HPE), which has affected Southeast Asia, particularly Peninsular Malaysia, for a long time. Such event can alter the photochemical reactions of secondary pollutants. This work investigates the influence of PM on ground-level ozone (O3) formation during HPE. Five continuous air quality monitoring stations from different site categories (i.e., industrial, urban and background) located across Peninsular Malaysia were selected in this study during the HPEs in 2013 and 2014. Result clearly indicated that O3 concentrations were significantly higher during HPE than during non-HPE in all the sites. The O3 diurnal variation in each site exhibited a similar pattern, whereas the magnitudes of variation during HPE and non-HPE differed. Light scattering and atmospheric attenuation were proven to be associated with HPE, which possibly affected O3 photochemical reactions during HPE. Critical conversion time was used as the main determining factor when comparing HPE and non-HPE conditions. A possible screening effect that resulted in the shifting of the critical transformation point caused a delay of approximately of 15–30 min. The shifting was possibly influenced by the attenuation of sunlight in the morning during HPE. A negative correlation between O3 and PM10 was observed during the HPE in Klang in 2013 and 2014, with −0.87. Essentially, HPE with a high PM concentration altered ground-level O3 formation

Thermal comfort and its relation to ventilation approaches in non-air-conditioned mosque buildings

This paper reports the outcome of a thermal comfort study that assessed the satisfaction of occupants with their surrounding thermal conditions. The study was carried out in 10 mosque buildings around lowland Nibong Tebal, Penang and highland Cameron Highlands, Pahang. It involved determining the compliance level of thermal comfort parameters (i.e. air temperature, relative humidity and air speed) at lowland and highland and establishing relationships between ventilation systems with predicted mean vote and predicted percentage of dissatisfied at lowland and highland according to ASHRAE Standard-55. The study was conducted from 1200h to 1700h/1730h to assess the thermal conditions of the 10 mosques during Zohor/Friday and Asar prayer times. During prayer times, an active ventilation system was in operation, while before and after prayer times, only passive ventilation (windows and doors) was available. Overall, findings indicated that better thermal comfort conditions occurred during prayer time at highland compared with those at the lowland, with the thermal sensation conditions of mosques in the former ‘slightly warmer’ to ‘slightly cool’ and in the latter ‘slightly warm’ to ‘hot’. Moreover, most mosques at lowland did not provide good thermal comfort because the percentage of dissatisfied was high compared to that at highland

Time effects of high particulate events on the critical conversion point of ground-level ozone

Particulate matter (PM), especially those with an aerodynamic particle size of less than 10 μm (PM10), is typically emitted from transboundary forest fires. A large-scale forest fire may contribute to a haze condition known as a high particulate event (HPE), which has affected Southeast Asia, particularly Peninsular Malaysia, for a long time. Such event can alter the photochemical reactions of secondary pollutants. This work investigates the influence of PM on ground-level ozone (O3) formation during HPE. Five continuous air quality monitoring stations from different site categories (i.e., industrial, urban and background) located across Peninsular Malaysia were selected in this study during the HPEs in 2013 and 2014. Result clearly indicated that O3 concentrations were significantly higher during HPE than during non-HPE in all the sites. The O3 diurnal variation in each site exhibited a similar pattern, whereas the magnitudes of variation during HPE and non-HPE differed. Light scattering and atmospheric attenuation were proven to be associated with HPE, which possibly affected O3 photochemical reactions during HPE. Critical conversion time was used as the main determining factor when comparing HPE and non-HPE conditions. A possible screening effect that resulted in the shifting of the critical transformation point caused a delay of approximately of 15–30 min. The shifting was possibly influenced by the attenuation of sunlight in the morning during HPE. A negative correlation between O3 and PM10 was observed during the HPE in Klang in 2013 and 2014, with −0.87. Essentially, HPE with a high PM concentration altered ground-level O3 formation

Indoor chemical air contaminants in main prayer hall during Jumaat prayer in mosques with different mechanical ventilation

Muslims generally pray five times a day. Every Friday, adult male Muslims congregate to perform Jumaat prayer, causing increased number of worshippers in mosques and vehicle movements. Consequently, indoor chemical air contaminants are produced inside and outside mosques. This study evaluated the compliance of indoor chemical air contaminants (CO, O3, TVOC, CH2O, and PM10) during Jumaat and Asar prayers in two mosques having different mechanical ventilations (i.e., air conditioning and non-air conditioned system) with the guideline limit recommended by Malaysia’s Industrial Code of Practice. Chemical air contaminants were monitored from 1200H to 1700H in the air-conditioned mosque and from 1200H to 1730H in the non-air conditioned system mosque, which were the times for Jumaat and Asar prayers. The monitoring was conducted from November 2016 to March 2017, during the Northeast monsoon. Results showed that the mean concentrations of the four chemical air contaminants in both mosques did not exceed the acceptable guideline limit. The mean CO, TVOC, CH2O, and PM10 concentrations in the air-conditioned mosque were 0.29 ppm, 354.09 ppb, 31.28 ppb, and 13.45 μg/m3; those in the non-air conditioned system mosque were 2.36 ppm, 344.32 ppb, 19.78 ppb, and 49.91 μg/m3, respectively. However, the air-conditioned mosque’s maximum PM10 concentration of 164.48 μg/m3 exceeded the acceptable guideline limit of 150 μg/m3. Moreover, both mosques’ mean O3 concentrations of 140 and 80 ppb exceeded the limit of 50 ppb, respectively. These results suggested that the concentrations of three chemical air contaminants (TVOC, O3, and CH2O) in the air-conditioned mosque were higher than those in the non-air conditioned system mosque possibly because of the inadequate ventilation system inside the air-conditioned building. Therefore, air-conditioned mosques should have a good ventilation system to provide suitable temperature and humidity for the Jemaah, as well as sufficient amounts of air to remove indoor chemical air contaminants

Effects of hoovering activities on biological contaminants and particulate matter levels in main prayer halls of Malaysian mosques

In Malaysia, carpets are commonly used as finishing flooring material in the main prayer hall of mosques. In cleaning carpets, hoovering has been the most popular method, but it directly triggers the uplifting of dust that may contain bacteria and fungi. Hoovering activities and ventilation strategies (air conditioning split units (ACSUs) or by active ventilation (non-ACSUs)) can affect the prevalence of bacterial and fungal growth. This study aimed to establish the total bacterial counts, total fungal counts and also PM10 concentrations under different ventilation strategies (ACSUs and non-ACSUs) in the main prayer halls of mosques. Identification of bacterial and fungal species also took place in this study. Sampling was performed in 25 mosque buildings (17 ACSUs and 8 non-ACSUs) with carpeted flooring on Zohor-Asar and Friday-Asar prayer sessions at Pulau Pinang, Malaysia. Results revealed that the total bacterial counts, total fungal counts and mean PM10 concentrations were higher in mosques with ACSUs than in mosques with non-ACSUs at concentrations ranging from 166cfu/m3 to 660 cfu/m3, from 118 cfu/m3 to 660 cfu/m3 and from 11.15 ± 9.32 µg/m3 to 49.30 ± 13.13 µg/m3, respectively. The total bacterial counts exceeded the acceptable guideline limit by the Industrial Code of Practice on Indoor Air Quality (ICOP), but the total fungal counts and PM10 concentrations did not. In some mosques, the total bacterial and fungal counts did not decrease even after hoovering activities were completed. The dominant types of bacteria found in the mosque buildings were Staphylococcus spp., Bacillus spp. and Micrococci spp., whilst the dominant fungal species was Aspergillus niger. Although the findings were not alarming, care should be taken by mosques authorities especially while and after hoovering, to ensure that, the indoor air quality in mosques are being maintained within the permissible limit to protect worshippers from being exposed to bacterial and fungal