Indoor Air Quality Assessments

Indoor Air Quality Assessments

Exposure to airborne contaminants in the indoor environment can result in a range of adverse health affects.  NSJ Enviro’s multi-disciplinary approach to assessing these potential exposures can identify the causative agents, including the exposure to other chemical contaminants such as formaldehyde, volatile organic compounds (VOCs) and dusts and synthetic mineral fibres.

HVAC systems may also contribute to many indoor air quality issues where ventilation in the building is poor.  If there is insufficient fresh air exchange or the HVAC system has not been maintained or serviced adequately, our thorough investigation of your HVAC system can highlight these potential issues and we can provide you with comprehensive advice to remove potential chemical contaminants and improve potential  health and comfort issues that may have arisen.

A typical IAQ assessment includes:

  • recording symptoms being experienced during a walk-through of affected and non-affected areas
  • inspection of the HVAC systems (air handling units, cooling, coils, drain pans, supply plenums and ducts, outside air intakes)
  • surface & air samples taken to detect mould
  • assessment of possible contaminant sources
  • measurements to evaluate air exchange and ventilation rate
  • recording of temperature and relative humidity to determine thermal comfort parameters

In most assessments this will highlight building—related problems. However, when further investigation and documentation is required, a sound sampling strategy is applied to field collection of additional data including air sampling for:

  • particulates
  • chemical contamination
  • bacterial and fungal counts

At NSJ Enviro we also understand the importance of meeting OH&S criteria in any organisation or business.  Through our assessment process, we are able to evaluate hazards and risks, plus provide recommendations to implement effective hazard and risk control measures.

IAQ Monitoring


Continuous Bioaerosol Samplers (CBS) are used to monitor the airborne concentrations of bioaerosols present in the air at your location. The system impinges bioaerosols onto an adhesive tape at 10 litres/min and the drum holding the tape rotates at 2mm/hour  –  one rotation/week.

The drum is returned to the laboratory each week where the tape is examined microscopically and the data reported graphically or averaged. Transient peaks in mould spores or other bioaerosol pollution can be detected and the time of occurrence pinpointed.

CBS Equipment can be used in:-

  • OH&S studies
  • Remediation sites where containment needs to be confirmed
  • Anywhere that unattended continuous bioaerosol detection is required
  • Locations where long term data is useful.