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.
Indoor air quality is a term which refers to the air quality in and around buildings and structures, in which it
is related to the health and comfort of those who are in the building. The study aims to identify the relationship
between environmental factors with microbe growth by investigating the concentration of airborne bacteria and
fungi at National Institute of Occupational Safety and Health (NIOSH) and to determine whether indoor bacteria and
fungi concentration were associated with environmental factors such as temperature relative humidity and carbon
dioxide concentration. This research was conducted concurrently with indoor air quality sampling as per requirement
under the Malaysian Code of Practice of Indoor Air Quality (COP IAQ). The COP IAQ requires minimum of one
sample to be taken from each area. If an area consists of a few separated rooms, each room is sampled and measured
independently. Also this approach was used to determine whether there is a difference of indoor bacteria and fungi
in different microenvironments. Results show that there is a significant correlation between humidity and bacteria
concentration and fungi concentration; and between temperature and bacteria concentration. However, there is no
significant correlation between temperature and fungi concentration. This study has also established significant
difference on bacteria concentration and fungi concentration between microenvironments.
Legionellosis is a respiratory infection caused by gram-negative bacteria known as Legionella. Although there are
many species of Legionella, the majority of all reported cases of legionellosis were caused by Legionella pneumophila.
Investigations of Legionella outbreaks comprised sampling building water systems for the presence of Legionella.
The aim of this study is to determine the isolation techniques with the most optimal yield for detection of Legionella
based on the Australian/New Zealand Standard Waters –Examination for Legionella (AS/NZS 3896:2008). This is an
experimental research, in which, Legionella species will be spiked in a bottle of water and various isolation techniques
will be conducted. As most cases of Legionellosis are caused by Legionella pneumophila group, this group of species
will be used.