Concern: Oakland Mills High School: October 10th, 2023 (CXOMHS20230002CD)

Location
Gym, Locker Room, and Room 103
Date of IEQ Report Form
Date of Report
Concern
Reported increase of a general health symptom. It stopped over the summer and returned now that the school year has started. I heard about the mold in the media center. Please also look at the gym, locker room and classroom 103.
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)
Findings

Date(s) of Assessment: September 26, 2023

Gym

The temperature (71.8 degrees Fahrenheit (F)) and relative humidity (49.3%) readings were acceptable. 

No Volatile Organic Compounds (VOCs) were detected. 

The wooden bleachers (including the underside) were assessed for visible mold growth. No mold growth was identified. 

Minor water staining was observed on the ceiling. The ceiling was screened with a thermal imaging camera. None of the staining was identified as an active leak.  The staining observed is historic and not believed to be a contributing factor.  The Office of the Environment spoke with the Building Maintenance (Roofing). The roof above the gymnasium was replaced in 2011/2012 and no leaks have been associated with the roof replacement.

The return vent on the left side of the gym (above the bleachers) is dusty. 

A stained ceiling tile was identified within the gym storage closet (double doors). 

Boys Locker Room

The temperature (73.5 F) and relative humidity (49.9%) were acceptable.

No VOCs were detected. 

A strong odor consistent with a boys locker room was sensed. 

The wall-mounted Heating Ventilation and Air Conditioning (HVAC) unit within the office area was observed to be clean and in good condition.

Minor damage was observed to the ceiling paint around the perimeter of the return vent (near locker room office). 

No sewer gas odors were sensed, particularly in the location of the shower drains. 

Various access panels are located in the ceiling (drywall). Several areas above the drop-ceiling were observed. No concerns or odors were identified above the drop ceiling.

Room 103

The temperature (72.6 F), relative humidity (59.9%), and VOCs (0.0 parts per million (ppm) were acceptable. 

The flexible ducts (HVAC supply) were connected. 

The nearby custodial closet was assessed. No concerns with chemical storage or odors were identified.  

Minor dust was observed on the supply diffusers. 

Minor settled dust was observed above the drop ceiling. This is not unusual. 

A drywall column is located in the room. No elevated moisture was detected in the drywall.

Room 103 is served by Air Handling Unit-1 (AHU-1). Three data loggers to measure carbon dioxide were placed in this zone. Carbon dioxide can be used as an indicator compound to determine is sufficient outdoor air is being delivered to a space. Outdoor air is important to indoor air quality as it dilutes contaminants that are produced in the indoor environment, such as odors released from people and the natural off-gassing of building materials and furnishings. It is these other contaminants that lead to indoor air quality problems such as odors and "stuffiness." Carbon dioxide is not generally found at hazardous levels in the indoor environment. No elevated carbon dioxide was identified in the three rooms within AHU-1. This suggests AHU-1 is providing adequate outside air. 

It should also be noted that various carbon monoxide (can cause headaches) readings have been taken throughout the school. No carbon monoxide has been detected. 

Heating Ventilation and Air Conditioning

The gym is served by AHU-10 and AHU-12. The locker room is served by AHU-12. Room 103 is served by AHU-1. 

AHU-10

  • The outside air dampers were open.
  • The coils could not be accessed (no access door).
  • The filters were acceptable. 

AHU-12

  • The outside air dampers were closed (deficiency).
  • The coils could not be accessed (no access door).
  • The filters were acceptable. 

Air Handling Unit-1

  • The outside air dampers were open.
  • The coils were acceptable.
  • No biological growth was identified in the drain pans, however the drain pans were showing evidence of corrosion (rust).
  • The filters were acceptable. 
  • Holes were identified in the connection between the unit and the supply duct and minor air leakage was identified from the unit housing.
  • General cleanliness of the AHU-1 penthouse was poor. 

Building Maintenance (HVAC) utilized a third-party engineering firm to assess the HVAC systems that are associated with the buildings original construction. The following recommendations were made in regard to the ventilation systems:

  • "All air handling units seem to have been properly maintained over the years and are in good condition, given that they are over 50 years old. However, they have far passed their service life and are presenting high levels of wear and tear. Therefore, we recommend that these units are replaced in lieu of retrofitting/repairing. Since the equipment has been maintained to such a level of care, they should still have several seasons of operation before they eventually fail."
      
  • Within the report, the Office of the Environment identified the following items that could have an impact on indoor air quality:
    • AHU-1: Air leakage from unit and the supply and return air side flexible duct connectors are brittle and have holes. 
    • AHU-10 and AHU-12: Flexible duct connectors are brittle and require replacement. 

Additionally, the following items were identified that could eventually lead to a potential future environmental concern: 

  • AHU-1 - The condensate pans are corroding. Should the pans fail, water will more easily leak from the units, potentially impacting building materials.
     
  • AHU-12 - A floor penetration was not sealed. Should a large leak occur in the penthouse, water could more easily travel to occupied portions of the building below.
     
  • Boiler Room - Corrosion was observed on an incoming cold-water pipe. If the pipe failed, the mechanical room (and possible beyond) could flood. 

Conclusion 

No contaminants of concern for the symptom reported such as carbon monoxide or VOCs were detected during the assessment. 

The most notable deficiency as it relates to air quality appears to be the outside air dampers being closed in association with AHU-12. 

Regarding AHU-1, in theory, the small holes in the duct connectors could potentially impact the amount of air being supplied to occupied areas. This could impact temperature control and potentially slightly reduce the amount of outside air being delivered to occupants in the zone. However, the carbon dioxide readings do not suggest an insufficient amount of outside air being delivered to the AHU-1 zone. With that being said, any potential reduction in outside air should be corrected in an effort to improve indoor air quality. 

The minor dust on the supply diffusers is very common in the built environment and is considered a housekeeping item (i.e. not anticipated to be a significant indoor environmental quality concern). Custodial Services is responsible for dusting the supply diffusers as needed. 

Information regarding the mold finding and the corrective actions associated with that finding can be found in association with IEQ Concern #CXOMHS20230002BE.

Corrective Actions
September 27th, 2023

AHU-1 and AHU-12 - Building Maintenance is in the process of replacing the flexible duct connectors to reduce air leakage. 

September 27th, 2023

AHU-1 - Replace condensate pans

September 27th, 2023

AHU-12 - Seal floor penetrations in penthouse. 

October 26th, 2023

Building Maintenance (HVAC) is to assess/address the cause of the outdoor air dampers being closed in AHU-12. 

October 30th, 2023

AHU-1 Penthouse - Building Maintenance (HVAC) improved the housekeeping within the penthouse. 

October 31st, 2023

Boiler Room - The condition of the cold water piping will be further assessed by the Office of Building Maintenance. Piping and components will be repaired or replaced as required. 

November 8th, 2023

Custodial is to clean the return vent (above bleachers) in the gymnasium and the supply diffusers in Room 103.

November 8th, 2023

Custodial Services is to place a work order for Building Maintenance to address the stained ceiling tile in the Gym Storage Closet if a work order is not already in progress. The tile can be changed following the repair. 

Closed
No
Tracking Number
CXOMHS20230002CD