No abstract

In Malaysia and many other Asian countries, countless number of restaurants are made of open or semi-open air buildings. These restaurants are commonly located beside roads, factories, and construction sites. The foods are often exposed to the air, increasing their tendency to be contaminated due to poor indoor and outdoor air quality. There are very few studies characterising and comparing the levels of indoor air pollutants in restaurants. Other than that, scarce data are available on dining establishments especially in the presence and absence of water mist application system. Due to these reasons, no best practices or guidelines can be developed. Hence, this present study aimed (1) to assess and compare the physical indoor air quality (IAQ) characteristics and airborne pollutants between different types of restaurant settings; (2) to identify microbes isolated in the presence and absence of water mist system; (3) to analyse bacterial counting within and between the different restaurant settings; and (4) to determine the relationship between physical IAQ characteristics and airborne microbial contaminants. Instruments known as Dustmate and VelociCalc® Multi-Function Ventilation Meter 9565 were used to measure the physical IAQ characteristics and airborne particulate matters. On the other hand, Surface Air System Indoor Air Quality (SAS IAQ) was use to seize the microbial contaminants. All the data obtained were compared with the standard reference known as the Industrial Code of Practice on Indoor Air Quality (2010) constructed by the Department of Occupational Safety and Health (DOSH). This study later indicated that the level of indoor PM10 concentrations was influenced by changes of physical IAQ parameters at the two restaurants investigated. As the PM10 increased, the colony forming unit (CFU) counting also increased. Although microbial contaminations were found during both periods of exposure (i.e., in the presence and absence of water mist) at both restaurants, significant relationship between the parameters measured cannot be determined. The bacterial species obtained during the presence and absence of water mist application system for both of the restaurants were also identified. Gemella morbillorum was found as the most dominant species, followed by other species such as Aerococcus viridans, Globicatella sanguinis, Leuconostoc spp., and Proteus penneri.

Library contains huge collection of books that can undergo biodeterioration process after period of time. Due to this  biological reaction, the existence of airborne particulate matters and microbes in the air of the library can be disturbed and elevated, thus can cause health implications to occupants. Therefore, it is an urge to assess and understand the correlation between physical indoor air quality (IAQ) characteristics, airborne pollutants and microbial contaminants in different library settings and locations. This study was carried out at three different libraries, which are Library A (Gambang as suburban area), Library B (Kuantan as urban area) and Library C (Pekan as rural area). The physical IAQ characteristics and particulate matter (PM) monitoring were assessed by using IAQ Meter and DustMate respectively. Surface Air System IAQ (SAS IAQ) was used to collect the airborne microbes. The microbial contamination was further assessed and identified in the laboratory by using API 20E and API 20 Strep while SPSS was used to analyze the relationship of physical IAQ characteristics, airborne pollutants and airborne microbes contaminants. The scientific method protocol and standard reference limits were compared based on Industrial Code of Practise on Indoor Air Quality, 2010 (ICOP, 2010) regulated by the Department of Occupational Safety and Health (DOSH). Respirable PM in Library A and CFU counts in Library A and C exceeded the standard limit with the value of 0.30 mg/m3, 2744 CFU/m3 and 1833 CFU/m3 respectively. Significant differences (p <0.05) between the selected libraries were observed among relative humidity (p=0.001), inhalable PM (p=0.001), thoracic PM (p=0.001), respirable PM (p=0.01), CO2 reading (p=0.001) and CFU counts (p=0.01). This study demonstrated Library C has poor air quality as the reading for CO2 and CFU counts are very high compared with the other two libraries. The bacterial identification findings indicated that Gram positive bacteria were abundant compared to Gram negative bacteria. Aerococcus viridans is the most dominant type of bacteria isolated in all the libraries.

Laboratory usually refers to a room or building equipped with chemicals and biological agents for scientific experimentation and research. Due to its own indoor hazards and its cause of health implications, it is an urge to assess and to understand the physical indoor air quality (IAQ) characteristics in the laboratory and the variables affecting the degree of exposure to occupants. The main objectives of this study was aimed to assess and to compare the physical IAQ characteristics and airborne pollutants including particulate matters (PM) and gaseous pollutants between laboratories, to identify microbial contaminants via bacterial counts as well as scientific bacterial-kits species identification and to correlate the relationship of physical IAQ characteristics, airborne pollutants and microbial contaminants between different laboratory settings within the same building which are Natural Product (NP) laboratory, Plant Tissue Culture (PTC) laboratory, and Microbiology laboratory. The physical IAQ characteristics and airborne PM was measured using VelociCalc multi-function ventilation meter 9565 and DustMate environmental dust detector respectively. Surface Air System Indoor Air Quality (SAS IAQ) was used to capture the microbial contaminants and after that bacterial counting and identification were done. The scientific method protocol and standard reference limits were compared based on Industrial Code of Practice on Indoor Air Quality (ICOP) (2010) regulated by the Department of Occupational Safety and Health (DOSH). The temperature of PTC laboratory, velocity of NP laboratory and Microbiology laboratory, the respirable particulate matter (PM) of all three laboratories and Colony Forming Unit (CFU) count of PTC and NP laboratory exceeded the standard limit regulated by DOSH. This study demonstrated that Gemella morbillorum is the common bacterial species available in the environment with poor IAQ and there is a significant relationship between physical characteristics, airborne pollutants and microbial contaminants between the different types of laboratory settings. In conclusion, priority should be given to NP laboratory as it is exposed to poor IAQ conditions and immediate action should be taken to eliminate the problems.