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)
Dates of Assessment(s): July 14, August 7, 10, 14, 24, 31, and September 1, 8, 21, 2020.
On July 14, 2020, the Office of Environment was performing the school's annual IEQ inspection and noted an odor and damp carpet in room 104. Room 104 is in a wing where there had been recent past history of summer time related mold growth. As a result, this wing and other areas experiencing past mold growth were placed on a weekly mold watch.
On August 7, 2020, the start of minor mold growth was observed in rooms 99 (student chairs, corner of a wall, and a metal AV cart), 141 (edge of student desks), and 143 (under two work tables). Building Services HVAC Shop and school were notified.
On August 10, data loggers collecting relative humidity and temperature trends were placed in rooms 99, 104, 141, and 143.
On August 14, 2020, dehumidifiers were placed in rooms 99-112 and 131-143 (odd number rooms) to prevent further mold growth until Building Services was able to evaluate and address the ventilation systems serving these areas.
On August 24, 2020, the Office of Environment did a final detailed mold inspection to address any further/additional mold growth. The mold growth was kept at bay by the dehumidifiers, however a few minor spots were on surfaces not previously inspected. These were disinfected upon observation. Custodial staff cleaned and disinfected all surfaces in room 99 and student desks in room 141 during the week of August 24th. Room 143 was cleaned and disinfected by the Office of Environment.
On September 1, 2020, the dehumidifiers were shut off in order to assess how the ventilation system was operating since being set back to normal operation due to limited scholol staff entering the building.
On September 8, 2020, the Office of Environment determined dehumidifiers could be removed from the school due to improving conditions and upcoming seasonal weather changes. The Office of Environment continued weekly visits.
September 21, 2020, conditions remain stable and data loggers removed. The Office of Environment will visit once more before October 15, 2020 as ventilation system should be in heating mode.
The cause of the growth was related to system design, weather conditions, and lack of sensible heat load (people, lights, etc.) during the summer break. Manipulation of ventilation unit operation and periodic surveillance will be performed next summer in attempt to resolve the recurring issue.