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 31, September 6, 9, 13, 14, 15, 21, 27, 28, and October 7, 2022
An individual indicated odor was detected this past June and may have been present prior, but was wearing face covering. The odor was again noticed upon returning to school this past August. The odor is described as fish like and is noticeable every day, especially during late afternoon.
The room consists of carpet, drop ceiling, cement block wall (CMU), and metal roof deck. The CMU walls go all the way up to the roof deck making the plenum space above the room self contained. Assessments were performed when the ventilation system was both on and off.
August 31 (mid morning visit)
Visit made when class was in session and did not detect an unusual or outstanding odor. Classroom sink had water within the drain trap (dried out drain traps can emit odor). The roof top ventilation unit (RTU) serving the room along with other room's within the back portion of the building had no deficiencies. The RTU's outdoor air dampers were open, no odor detected within the RTU, and filters, coils, and condensate pan were found to be in acceptable condition. The RTU's heat recovery wheel was in acceptable condition and not spinning at the time of inspection (spins below 50 and above 80 degrees Fahrenheit).
September 6 (early morning visit before occupancy)
An odor was not detected within the room below the drop ceiling. The wood casework along the room's exterior wall was dry as determined by the use of a moisture meter (wood setting). The casework was well sealed (caulked and tight against) to the wall. A wall chase (housed piping to a past wall ventilation unit within the classroom) near the exterior exit door was assessed from above the chase. No odors detected, and no openings (in concrete slab) within the chase. The old piping was present and disconnected, but top ends were open.
The room was compared to rooms within the wing and an identical room (room 70; near a restroom and walls up to the roof deck). No unusual and/or outstanding odors were detected within the rooms used for comparison. Adjoining classrooms (i.e. room 66) had a shared open plenum space above the drop ceiling (not self contained like room 67).
The school's roof was replaced in phases over the last three summers. The classroom shares a wall with the boy's restroom. An abundance of roofing debris was observed along this shared wall. The shared wall does not house plumbing for the restroom (sinks and toilets on opposite wall within the restroom). The classroom's sink and restroom sanitary vent pipes were connected and vented through the roof.
At the shared wall with the restroom, the corrugated roof deck had open ends / flutes. Room 70 (comparable room) did not have open flutes and any gaps atop or between the CMU, and the roof deck had been sealed with mortar.
An odor could be detected above the drop ceiling of room 67. The odor was similar to fiberglass (damp) and/or new ceiling tile. The inspector asked the person with the concern to smell the space above the drop ceiling to confirm if the odor was the same as what they detect within the room. They confirmed the odor was the same, but not as strong.
September 9 (morning visit before school day)
The pressurization of the plenum space above the drop ceiling was very positive (blowing air down into classroom) compared to the classroom space when testing at a removed ceiling tile. Room 70 plenum space was negatively pressurized. Air pressurization was tested with the use of smoke tubes.
An infrared camera was used to look for thermal anomalies within the roof / roof deck. No issues were detected, however, cold temperatures were noted at the open flutes of the corrugated roof deck. Air movement (qualitative and with smoke tubes) during the investigation showed positive and negative air pressurization /movement from the open flutes.
September 13 (morning visit before school day)
The purpose of the visit was to detect odors and check air pressurization of rooms and above drop ceilings. No outstanding odors detected. However, the odor that had been detected above the drop ceiling in room 67 was strongest near the wall shared with the boy's restroom. The smoke tests determined air pressurization was variable.
September 14
Building Maintenance assisted by reviewing mechanical blue prints. As a result, they removed casework along the exterior that once contained a wall ventilation unit. A condensate drain was observed and was stuffed with fiberglass (not properly abandoned). At the time, the condensate from the ventilation units in the back wing drained into storm water system. Odors could emit from this open drain. Building Maintenance sealed the drain opening and placed back the case work. The wall chase and case work did not share an opening and the case work had a solid base around the drain opening. If an odor occurred from the old condensate drain, it appears it would have been well contained/confined to space below case work. Building Maintenance did not observe moisture damage (water vapor coming from drain) at the casework near the drain. The teacher noted days later that the odor was still present after sealing the condensate drain.
September 15 (morning before increasing outdoor temperatures)
The Office of Environment collected samples of the roof debris on the back side of ceiling tile, foiled wrap fiberglass ventilation insulation, and ceiling tile. These items were placed in zip lock baggies and place in a warm environment to determine if an odor was produced from these items similar to the odor within room 67. No odor was detected from these items over time.
The exterior roof was assessed (visual and infrared camera) since the roof deck flutes were open and odor seemed strongest above the drop ceiling at the shared wall with the boy's restroom. A bubble was observed and the infrared camera showed heat from the building along the length of the shared wall with boy's restroom. Building Maintenance indicated this was a roof expansion joint (did not investigate if existing or installed during the roof replacement) and is expected.
September 21 (late afternoon; no class in session; warm day)
The odor that was detected above the drop ceiling could be detected within the room (below drop ceiling). The individual was present and confirmed the odor was present. A ladder was used to gain access as close as possible to open flutes of the roof deck. The inspector could not get close enough to determine if odor was coming from the open flute ends. However, it was noted that the odor was stronger near this wall and air movement could be seen (i.e. disturbance of cobwebs) from flutes and gaps around cinder blocks where roof trusses set. The exterior wall above the drop ceiling was missing mortar between some cinder blocks.
September 27
Building Maintenance had their roofing contractor spray foam the flute openings of the roof deck and spacing between roof trusses and cinder block. Polyurethane caulk was used to fill in the missing mortar which was minimal. In addition, they cleaned the roofing debris from above drop ceiling.
September 28 (morning visit before occupancy)
The Office of Environment inspected above the drop ceiling. All work was completed and acceptable.
October 7
The odor of concern was not present and the individual reporting the concern has not smelled the odor since roofers sealed requested voids. However, the weather has been cooler since the work was completed. Cooler weather may suppress the odor where warm weather may exacerbate.
Building Maintenance remove casework to identify an abandoned condensate drain from a previous existing unit ventilator. Drain opening sealed and casework placed back.
The open ended pipes in the wall chase once serving an unit ventilator were capped as an extra precaution.
Roofing contractor sealed roof deck open ended flutes and spacing around roof trusses with spray foam. They filled in missing mortar on exterior wall using polyurethane caulk.
Please contact the Office of Environment if the odor reoccurs.
The issue was re-assessed in 2023. A strong odor was emanating from beneath the casework. A board-approved restoration contractor removed the plugs installed by Maintenance and filled the drain pipes with concrete and then re-installed the plugs.