Concern: Northfield Elementary School: September 21st, 2018 (CXXNES201800004F)

Room 145
Date of IEQ Report Form
Date of Report
There is excessive humidity in the classroom. There was mold detected during the summer of 2018 and believe that the conditions that led to the mold still exist. It is extremely muggy and uncomfortable. The concern was originally submitted on September 14, 2018 by the individual using the previous reporting method.
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 Investigation:  September 21, 2018 and review of a data logger recording temperature and relative readings from August to October 2018.

Mold growth was not observed on inspected surfaces.

A musty or an unusual outstanding odor was not detected.

The carpet was dry as determined with the use of a moisture probe.

The exterior wall did not exhibit signs of moisture intrusion.  The casework along the exterior wall was dry as determined with the use of a moisture meter calibrated for wood.

The condition (i.e. roof deck, pipe insulation) above the drop ceiling was acceptable.

The ceiling tiles were in good condition.

Overall housekeeping of the classroom was acceptable.

The room is served by Roof Top Unit  2 (RTU 2).  The cooling coils had minor particulate buildup.  The outdoor air dampers were closed.  No signs of current or residual condensate present in condensate pan and the end of the exterior condensate drain line was dry.  The air conditioning compressor came on only for a short time which may be an indication of the room cooling too quick, thus not removing an adequate amount of humidity from the room.

The data logger indicated favorable conditions for mold growth due to continuous elevated humidity within the room.  A dehumidifier was placed in the room for a week to break the elevated relative humidity cycle to prevent mold growth.

Once the dehumidifier was removed, the data logger indicated that the review, work, and/or adjustments Building Services previously made to the RTU and controls did not improve the relative humidity within the classroom during moist (air) weather patterns.

Corrective Actions
September 24th, 2018

Per work order 88222, Building Services checked over the RTU and it was operating as expected.  The refrigerant level, amperage draw on condenser fans and compressors were acceptable.  The fan belt was in good condition.  The cooling, condenser, and evaporator coils were cleaned.  The outdoor air dampers were checked and found not to be operating. 

Additional work was performed on September 26, 2018 to complete the review and verify the RTU was operating per control settings.

Building Services and the Office of Environment will continue to monitor the situation during the cooling season and make necessary corrections to eliminate excessive humidity levels within the classrooms. A review of the design of the system will also occur.

Date Closed
Tracking Number