The proliferation of indoor airborne microorganism in public institutional buildings such as schools and universities is often regarded as a potential health hazards to the buildings’ users. This issue is not new in Malaysia, a country with humid climate which favours the growth of microorganism. However, there is lack of research’s data, especially in higher institutional buildings in this country. The assessment of the indoor air quality is conducted in a university’s two new commissioning buildings located at Southern Peninsular of Malaysia. Both buildings utilized centralized air conditioning system. Concentrations of airborne microorganism were determined using a single-stage impacter (biosampler) as per requirement of National Institute of Occupational Safety and Health (NIOSH) Manual Analytical Method 0800. The acquired readings were compared to the standard level determined in Industry Code of Practice on Indoor Air Quality (ICOP IAQ) 2010. Other parameters such as relative humidity, temperature, and air velocity were recorded along the assessment. The mean concentrations of the total bacteria at the affected area of the two buildings are 1102.5 CFU/m3 and 813 CFU/m3 respectively and it is significantly higher compared to the maximum exposure limit of 500 CFU/m3. While, the mean concentration of total fungi at the affected area for two buildings are 805.7 CFU/m3 and 509 CFU/m3 respectively which are both higher than the reading of outdoors and unaffected indoor area although slightly lower than the maximum exposure limit of 1000 CFU/m3. This study provides a glance of the poor indoor microbiological air quality in new higher institutional buildings in this humid region.

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Mosaic sludge is sewerage from mosaic industrial activities such as cutting, polishing and grinding. This sludge mostly will be disposed directly to landfill and some of it was discharged in drainage system without proper treatment. Therefore, in this study, mosaic sludge from the mosaic industry were reused and incorporated into fired clay brick in order to provide alternative disposal method, producing adequate quality of brick as well as minimizing the heavy metal leachability to the environment. First, X-Ray Fluorescence (XRF) was conducted to determine the heavy metal concentration from two types of mosaic sludge. The results indicate that the highest element concentration in mosaic sludge (BS and PS) shows that Barium is the highest with 3253ppm and 3260ppm. On the raw sludge, the lowest obtained in BS and PS is Cesium with 14ppm and 17ppm. SPLP and TCLP also conducted in this study and the results show that, even though the element such as ferum (Fe) and cadmium (Cd) was not detected in XRF but in SPLP and TCLP, it shows that these two elements exist in clay, BS and PS with low concentration. In term of properties, compressive strength was conducted by incorporating 0%, 1%, 5%, 10%, 20% and 30% bodymill and polishing sludge into fired clay brick. The results show that compressive strength of BS brick was stronger than PS brick. Lastly, Static Leachate Test (SLT) was conducted to measure the long term leachability of heavy metals from different percentages of mosaic sludge brick. In SLT result, ferum (Fe) shows the highest value of heavy metal concentration among other elements. The results for control brick, BS brick and PS brick show the same pattern and far from the limit set by USEPA.