Indoor air quality (IAQ) can be described as the quality of air weather inside or surrounding the buildings and structures
which are associated with the health and comfort ability of occupants in the buildings. The level of IAQ in buildings can be influenced
by microbial contaminants activities, chemicals exposure and allergens that seriously can create health effects to the building’s
occupants. In the present study, the effect of environmental factors such as temperature and relative humidity on the optimum growth
of Aspergillus niger (A. niger) was investigated. The study revealed that the optimal fungal growth of up 43mm in diameter was
evidenced under room temperature of 30oC at the end of a five day incubation period. However, the relative humidity from 40% to 90%
applied is able to support the growth of the A.niger. The relative humidity of 90% shows the optimal effect where 56 mm of diameter
growth happened after 5 days of incubation. The significant finding to emerge from this study is that environmental factors such as
temperature and relative humidity do affect the growth of A.niger. The optimal temperature and relative humidity for A.niger to grow
are 30oC and 90%, respectively.
The paper focused on the examination and testing of local exhaust ventilation (LEV) systems at one of Electrical Company to check the transport velocity whether it meet the recommended American Governmental Industrial Hygienist (ACGIH) Standard. The industrial hygiene approaches, AREC (Anticipating, Recognize, Evaluate and Control) were adopted in this study. This is to ensure that the LEV system installed has the optimum efficiency to extract out the contaminants from the workstation. Objective of this study is to make comparison with previous and current monitoring data. The efficiency and the other parameter measured will be the main source to analyze for the particular applications. The differential of data was discussed and several recommendations are proposed to make sure the LEV system performance is excellent.
This paper discuss thermal comfort studies of an under air conditioning in hot and humid climate which at one of the higher institution in East Coast of Malaysia. Indoor thermal environment is important as it affects the health and productivity of building occupants. The paper reports on an experimental investigation of indoor thermal comfort characteristics under the control of air conditioning. Firstly, the well known Fanger’s thermal comfort model was simplified for the current experimental investigation. This is followed by reporting the experimental results of indoor thermal comfort characteristics under the control of temperature, with eight different of temperatures which are 22oC to 29oC. Finally, indoor thermal comfort was merely affected by the increment ventilation and outdoor climate. PMV value was higher when near from the window because of the effects of the wall radiations and the metabolic heat.
There are several alternative sampling and analytical methods available for the determination of respirable
crystalline silica exposure among workers. The commonly used ones are, (1) NIOSH Manual Analytical Method
No.7500(NMAM 7500) which is Silica, crystalline, by X-ray difractometer via filter deposition(NIOSH 2003), and
(2) MDHS 101 (Methods for the Determination of Hazardous Substances (MDHS) Guidance No.101: Respirable
crystalline silica in respirable airborne dust). The aim of this study is to compare applicability of respirable crystalline
silica sampling and analysis between method MDHS 101 and NMAM 7500. Laboratory procedures will be performed
strictly based on MDHS 101 and NMAM 7500. Both methods apply X-ray diffraction as analytical technique with
many variations on sampling techniques and laboratory preparations. Quality assurance values such as detection
limits, accuracy and precision are derived from both data and will be compared to determine which of the method
establishes better quality assurance. The method which establishes better quality assurance will be recommend to be
used in Malaysian respirable crystalline silica monitoring programme. The strength of this research lies on its potential
to provide local capabilities in analysis of respirable crystalline silica in Malaysian setting.