Identify deficiencies that may impact IEQ and/or sources of odor concerns. Typically includes the following depending on the nature of concern, but not limited to:
- interview/questionnaire of concern individual(s)
- inspection above drop ceiling (condition of roof deck, pipe insulation, return air plenum)
- inspection of ventilation system (operation of variable air volume box and outdoor air dampers, check controls, measurements of carbon dioxide, temperature and relative humidity, sources near outdoor air intake, measure return and supply air volume, cleanliness of coils, liner and condensate pan)
- inspection of exterior
- inspection below drop ceiling (housekeeping, sink and floor drain traps, signs of past and present moisture concern via visual and/or moisture meter, mold growth, ensure connection of current and capping of abandoned sanitary vents, odorizers, excessive plants and fabric items, identify potential pathways, and measure volatile organic compounds, carbon monoxide, and lighting)
Date of Assessment: July 13, 2026
The administrative area was observed to contain carpeted floors, drywall walls, and drop ceiling tile.
Temperature, relative humidity, and carbon dioxide readings were collected and found to be acceptable.
The carpet was evaluated for moisture using a moisture sensor. No elevated moisture was identified in the carpet.
The drywall walls were evaluated using a moisture meter. No elevated moisture was identified within the walls.
Visible mold growth was observed on the upper (plenum-facing) surfaces of the supply air diffusers.
Subsequent investigation determined that approximately 30 supply air diffusers within the area served by Air Handling Unit 5 (AHU-5) exhibited similar growth. No comparable conditions were identified in areas served by other air handling units during the assessment.
Inspection of AHU-5 identified a restricted condensate drain line, resulting in the accumulation of condensate within the drain pan and periodic overflow into the interior of the air handling unit.
Although a definitive causal relationship could not be established based on the conditions observed during the assessment, the fungal growth identified on the supply air diffusers is considered likely to be associated with elevated moisture conditions within the ceiling plenum resulting from condensate overflow from AHU-5. The introduction of excess moisture into the plenum, combined with temperature differentials between the conditioned supply air diffusers and the surrounding plenum environment, likely promoted condensation on diffuser surfaces, creating conditions conducive to fungal growth.
Found debris in drain pan accumulated right before the exit point to the trap, causing the water to back up into the drain pan. Cleared debris around exit point allowing water to drain properly.
A board-approved remediation contractor performed cleaning and decontamination of the affected supply air diffusers and adjacent surfaces using a disinfectant.
Multiple air scrubbers equipped with High-Efficiency Particulate Air (HEPA) filtration were deployed within the work area to capture airborne fungal spores generated during remediation activities.