Note: The Office of the Environment has recently transitioned to a new Online IEQ platform (as of August 2018). The new platform does not allow the back-dating of IEQ concerns. This concern is inappropriately dated January 11, 2019. The concern should be dated August 28, 2018.
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: August 29, 30, 31, September 5, 11, 15, and 17, 2018.
The portable wing contains two restrooms and nine classrooms. The findings provided below are generalized (may not apply to all rooms) for the the entire portable.
Relative humidity mold growth was observed only on wood surfaces of newly purchased furniture (work tables and student desks) and no other furniture or supplies within the classrooms. The new furniture was delivered this summer and stored in the school's gymnasium. It was undetermined if the mold growth occurred while stored in the gym (see IEQ Report dated 9/29/2018) or delivered as such, but not believed to be due to conditions in the portable based on amount of time in the portable and no other surfaces were observed to be impacted.
A must odor was present. The intensity of the musty odor ranged from non-existent to very strong depending on the classroom.
Carpet surfaces were moist at times in various rooms as determined with the use of a moisture probe.
At times, student desk tops in some classrooms were wet to the touch via condensation (surfaces reaching dew point).
Thermostats were not immediately reprogrammed (temperature set points and time of day) when the portable wing was relocated to the site this summer.
During the time period of concern, weather consisted of very high relative humidity and dew points for an excessive and continuous period of time. Outdoor air temperatures were lower than normal.
Each room has it's own ventilation unit and thermostat. The ventilation units have outdoor air dampers which were controlled to open based on indoor carbon dioxide levels (exhaled by occupants). Outdoor air is introduced to reduce body odors and stuffiness. As a result of weather and ventilation operation, unconditioned air would enter the classrooms without needing to cool or heat which would typically assist with dehumidifying the air.
During the investigation and before adjusting thermostats and ventilation controls, indoor relative humidity readings were 70% or above for continuous bouts of time.
The services of remediation contractors were utilized to clean the mold growth and provide dehumidifiers until the environmental conditions were stable and extreme weather ended.
Mechanical contractor positioned supply air diffusers not to blow onto the thermostats in order to prevent short cycling (satisfies thermostat set point for cooling too quickly without adequately dehumidifying).
Building Services and mechanical contractor reviewed and adjusted thermostats and ventilation unit controls to better address the extreme weather period.
The Office of Environment performed at least weekly checks of the classrooms for mold growth, relative humidity, temperature, and carpet moisture until weather broke and/or ventilation stabilized the indoor environment.
The Office of Environment will revisit and monitor as necessary during this coming summer.