November 20, 2018

Indoor Air Quality and Commissioning

How is the indoor air quality (IAQ) in your workplace, school or home? Why does it matter?

Well, it is estimated that most people in Canada spend about 90% of their day indoors. And the IAQ of that space directly affects your health, comfort and productivity.

Exposure to increased levels of indoor pollutants can lead to adverse health effects, including increased allergy and asthma symptoms, colds, headaches, fatigue and “Sick Building Syndrome”. Indoor pollutants include a mix of outdoor pollutants and indoor contaminants such as emissions from building materials and furnishings, combustion sources (i.e. burning fuels for building equipment), cleaning products and activities of building occupants.

In most buildings, IAQ is managed by the heating, ventilating and air conditioning (HVAC) system to provide the required outdoor airflow rates, air filtration, contaminant dilution, exhaust of contaminants at the source and to maintain space temperature and humidity levels within reason.

Well-designed HVAC systems are critical to providing good IAQ; however, the installation, commissioning and maintenance of these systems is critical to ensure the design intent is realized.

During our commissioning functional testing, we verify the operation of the HVAC systems to ensure they are operating as designed. Some of the operational items we look at include:

  • Correct air handling equipment sequences of operation
  • Outdoor air and exhaust air damper control and modulation
  • Correct operation/control of energy recovery equipment
  • Correct operation of interlocked equipment (supply/exhaust fans)
  • Space temperature verification
  • Space humidity verification
  • Space CO2 reading verification

While on-site, we also keep an eye out for any site conditions that may affect IAQ. Conditions include dirt or debris in ductwork, condition of filters in air handling equipment and adequate removal of condensation from cooling coils. Another frequent issue is build-up of moisture/condensate in ductwork near humidifiers.

Once performance testing is completed and we are satisfied that the HVAC systems are performing as per the design, it is important these conditions are maintained. We will ensure a detailed Systems Operation Manual is provided to the build Operator. The manual will contain all of the necessary information on how the HVAC systems should operate and what regular maintenance tasks are required.

Well maintained and proper functioning HVAC equipment is important to provide good indoor air quality for building occupants’ health and well-being.

Nicole Stoangi, P.Eng.

Why Commissioning