Case 1

Building Lecture Hall at Tertiary Institution
LocationCeiling board
Ventilation modeCooling by air-conditioning
Sampling MethodTape sampling, Culturing
No. of Tape Samples1
No. of Cultured Samples (from tape)4
Medium UsedPotato Dextrose Agar (PDA)

Temperature (°C): 22.5
Relative Humidity (RH): 56.7
Wind Speed (m/s): 0.21

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Building

Renovation encompassed the changing and installation of the false ceiling system outside the air-conditioned lecture hall at the academic institution. Airborne materials were able to spread to the adjacent lecture hall through the Air Handling Unit (AHU). Measures to prevent such exposure were lacking.

Observation

Films of dark-pigmented material can be seen on ceiling boards close to the diffuser outlet, soon after commencement of renovation works. Moisture held by the dust particles prior to infiltration may serve as moisture for the spores amongst the particles to grow. Closer observation reveals sparse dark-pigmented mouldy spots.

Identified Fungus

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