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)
The space was visited on numerous occasions in January to screen for a potential odor. No malodors were detected by the Office of the Environment during any of the walkthroughs.
The Office of the Environment spoke with Building Maintenance (Heating Ventilation and Air Conditioning (HVAC)) regarding the potential odor concern. Building Maintenance reported that there were belts in the HVAC system that needed to be replaced and that the potential overheating of the belts represented a probable cause for the reported odor. Building Maintenance reported that the belts had been replaced in Air Handling Unit-2 (AHU-2) on February 10, 2026.
Prior to February 10, the Office of the Environment also conducted a general assessment of the space. This included:
- Observing surfaces for visible mold growth and malodors. No visible mold or malodors identified.
- A thermal infrared camera screening. No thermal anomalies indicative of moisture intrusion identified.
- Moisture sensing of the carpet. No elevated moisture detected.
- Screening with a Photo-ionization detector. No Volatile Organic Compounds (VOCs) were identified.
- Observing above the drop ceiling for visual indications of water damage and/or malodors. No concerns identified.
- Assessing general housekeeping. In general, housekeeping was acceptable, however minor dust deposits were observed on the supply diffusers in the area. The assessor cleaned the supply diffusers upon the finding and also requested Custodial Services improve cleaning frequency.
- Assessment of other items that could impact indoor air quality.
- An air purifier with an Ultra Violet (UV) light function (brought in by staff member) was observed. These air purifiers can potentially produce ozone. Ozone has an odor and health effects similar to what is being reported.
- The Office of the Environment also assessed various other cubicles in the general area for items that could impact IAQ, to include air fresheners, disinfectant sprays, essential oils, etc. These items were not identifed.
The reported health concerns/odor were still being reported after the belt replacement, cleaning of the supply diffusers, and removal of the air purifier with UV function.
On February 12, the Office of the Environment collected three ambient air samples for analysis (TO-15) of Volatile Organic Compounds (VOCs). VOCs represent various organic compounds present in the indoor and outdoor environment and are ingredients various products such as varnishes, solvents, cosmetics, perfumes, and cleaning/disinfecting products.
The results of the sampling indicated various VOCs were present, which is expected. These VOCs were compared to Maryland Department of the Environment's Target Indoor Residential Targe Indoor Air Concentration. None of the VOCs collected in any of the samples were above the Indoor Residential Target Indoor Air Concentration. Note, that the residential concentration was used as it is more strict than the commercial target concentration, which would be more appropriate for this assessment.
Additionally, the VOCs were compared to the "VOCs Commonly Found in Normal Indoor Air of Office Buildings" which provides a typical range of VOCs in buildings as determined by a nationwide study performed by the Environmental Protection Agency (EPA). The VOCs detected during the sampling were either below or within the concentration range of "VOCs Commonly Found in Normal Indoor Air of Office Buildings. (Reference: The IAQ Investigators Guide, Chapter 6, What is Normal?).
Finally, the VOCs in each sample were added together to derive a Total VOC concentration (TVOC). "Typical total VOC concentrations found indoors range from 50 to 500 (ug/m3). TVOC concentrations within the complaint areas were well below 500 ug/m3 (226 ug/m3 and 130 ug/m3)
Additionally, on February 12, the Office of the Environment sent a communication to the various cubicles in the general vicinity requesting such items be removed.
Due to general health symptoms still being reported, the Office of the Environment located access panels in the ductwork associated with AHU-2 for further assessment. Discoloration that represented suspect mold growth was observed on the sound liner within the duct work. Later testing confirmed elevated mold. Approximately 20 square feet of mold growth was identifed on the sound liner within AHU-2.
The cause of the mold growth is believed to be associated with the air handling unit’s fan pulling condensation off the unit’s cooling coils during cooling season. The moisture is then distributed onto the porous insulation, which only extends approximately 13 feet from the air handling unit. Due to the porous nature of the insulation, it apparently remains damp for long enough to support visible mold growth at certain times of the year. This likely occurred over the summer months as the region experienced record high outdoor dew points.
A contractor certified by the National Air Duct Cleaning Association conducted a cleaning of the insulation within the air handling unit, to include contact cleaning, application of an EPA-registered disinfectant, and encapsulation. Staff from the HCPSS Office of the Environment were present during the remediation and confirmed the work was completed.
HCPSS Building Maintenance staff will further investigate and address the cause before the summer when we expect higher humidity. Part of this work will include removing the units coils for cleaning during an extended break (likely Spring break). The Office of the Environment will also continue monitoring the air handling unit weekly until Building Maintenance has addressed the root cause to ensure regrowth doesn't occur.