Educational environments require stable indoor air quality to support concentration, comfort, and overall well-being. This project involved ventilation system cleaning for a university lecture hall in Johor following reports of musty odours and declining air freshness.

Project Scope

• Air duct cleaning

• Diffuser cleaning

• AHU inspection

• Microbial surface assessment

The lecture hall serves high daily occupancy with continuous air circulation during academic hours. Over time, dust deposition within duct interiors and diffuser surfaces contributed to odour issues and reduced perceived air quality.

Issues Identified

During inspection and internal surface assessment, the following conditions were observed:

• Dust accumulation within supply duct sections

• Contaminant deposits on diffusers

• Early signs of microbial surface growth in selected areas

• Reduced freshness of supply air

Although airflow delivery remained operational, indoor comfort levels were impacted due to particulate recirculation and odour presence.

Technical Execution

Cleaning works were conducted using controlled mechanical agitation and negative air extraction methods to prevent cross-contamination within the occupied facility. Diffusers were dismantled, cleaned, and reinstalled to ensure unobstructed air distribution.

AHUs were inspected internally, with emphasis on:

• Coil surface condition

• Drain pan hygiene

• Internal insulation condition

• Moisture-related microbial risk zones

Surface checks were performed to identify microbial presence and ensure hygienic restoration standards were achieved.

Outcome

• Cleaner, fresher supply air

• Noticeable reduction in musty odour

• Improved occupant comfort within lecture spaces

• Enhanced ventilation hygiene for academic operations

Routine ventilation hygiene in educational facilities supports healthier learning environments and reduces the risk of IAQ-related complaints.