Air Quality Concerns

Maintenance problems

  • Broken thermostats
  • Misadjusted diffusers
  • Heating, cooling, or ventilation breakdown malfunctioning during building operating hours
  • Leaking fan coils
  • Odours due to maintenance and construction (roofing projects) in or around a building
  • Chemical type smells (e.g. drain/sewer gas, natural gas, vehicle exhaust)

What to do:

  1. Report the concern to the Plant Operations 24 hour service number (ext. 33793). 
  2. Inform your supervisor/administrator of the situation if problems continue after Plant Operations addresses them.

Air quality standards

Plant Operations ensure appropriate air quality is provided to all buildings by designing and maintaining building ventilation systems according to the Occupational Health and Safety Act (OHSA), the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE), and the associated applicable standards to Ontario. 

The following criteria are used to determine air quality:

Criteria UW Guidelines OHSA Regulations

Carbon dioxide

Up to 700 ppm above outdoor levels (up to about 1,000 ppm)

Maximum 5,000 ppm


25 to 60%
No regulation


19.5 to 25.5 deg C
Minimum 18 degree C

Air flow/movement

No regulation

Other specific agents are not included in determining building air quality. Potential exposures to specific agents are addressed in other programs (Occupational Hazards and/or Hazardous Material Spills).

Ongoing air quality concerns

Ongoing air quality concerns include those that are:

  • Chronic in nature (ongoing for more than three weeks)
  • From an unknown origin
  • Still of concern after being addressed by Plant Operations as a maintenance problem

What to do:

Review concerns with your supervisor/administrator who then reviews concerns with the department head to determine whether a department assessment should be conducted.

Department indoor air quality assessment

  1. Department appointee contacts the Safety Office with a description/summary of the issues identified.
  2. The Safety Office will provide direction and a reporting link to which departmental individuals can log their exposures.

If the findings of the department assessment support the concerns, the department head should address the concerns as follows:

  1. Issue Plant Operations a works request to address the concerns.
  2. Plant Operations will review concerns with the department and determine whether an air quality consultant (approved by Plant Operations) will be contracted to conduct a review.
  3. When an air quality consultant is contracted, Plant Operations will arrange pre-consultation meeting with the Safety Office, Plant Operations, and the consultant.
  4. If indoor air quality testing is required, the Safety Office will notify the appropriate Joint Health and Safety Committee of any scheduled testing.
  5. Results from the review, air quality testing, and resolution shall be reported by the department to the department personnel in the area of concern and to the Safety Office.
  6. The Safety Office will report results to the appropriate Joint Health and Safety Committee.