Concern: Ducketts Lane Elementary School: November 7th, 2019 (CXDLES201900012A)

Room C108
Date of IEQ Report Form
Date of Report
I have been experiencing severe respiratory issues in my classroom ever since the HVAC system had issues a few weeks ago. My symptoms improve when I'm at home and get worse when I come to school.
IEQ Investigation Process

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(s) of Assessment: November 15 and 19,  and December 9, 2019

The classroom contains drywall, a carpeted floor, and a drop-ceiling.

No elevated moisture was detected in the carpet or the drywall.

A thermal infrared screening was conducted. No thermal anomalies indicative of moisture intrusion were identified.

No odors were sensed.

Furniture and casework were assessed. No mold growth was identified. 

Temperature (73 degrees Fahrenheit), carbon dioxide (568 parts per million (ppm)), and carbon monoxide (0.0 ppm) were acceptable.

Relative humidity would be considered low (24.5%), however this is typical for HCPSS schools as the ventilation system does not humidify air before introducing it to occupied spaces. Humidification can introduce clinical health conditions such as humidifier fever.

The Air Handling Unit that services the space was inspected. The filters, coils, and drain pan were in excellent condition (recently constructed in 2013). The outside air dampers were open.

Building Services (HVAC) reported that they are having an issue with the Dedicated Outside Air Unit (DOAU-2) that services the space. Issues with controls and short-cycling are noted. As it relates to IEQ, short-cycling is the most significant, particularly in the spring and summer. Short-cycling can cause elevated relative humidity within the building (if the outdoor humidity is also elevated). However, as it is currently Autumn, elevated indoor relative humidity is unlikely due to low outdoor humidity.

After learning of the short-cycling, the Office of the Environment inspected the remaining rooms serviced by DOAS -2. No relative humidity mold growth was observed on the surfaces assessed.

Areas above the ceiling were assessed. No concerns with mold, moisture intrusion, or significant fireproofing delamination were observed.

Corrective Actions
October 31st, 2019

Building Services (HVAC) determined the compressor on the unit is short-cycling due to it being oversized. Building Services (HVAC) modified the controls to reduce the potential for short-cycling. Building Services is to monitor the humidity with data loggers during the Spring/Summer of 2020 to determine the effectiveness of the controls modifications.


Date Closed
Tracking Number