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Ventilation and air quality testing


BRANZ tests natural and mechanical ventilation in a range of buildings. We measure air pollutants to assess indoor air quality and test the performance of ventilation systems.

BRANZ staff have a detailed understanding of natural and mechanical ventilation. We are involved in specialised research into how occupants use buildings and the effects of ventilation failure (especially its contribution toward condensation and mould).

Findings from BRANZ testing have provided scientific evidence for developing New Zealand Building Code requirements and standards for indoor air quality and ventilation efficiency.

Using blower door or tracer gas methods, we can measure the ventilation rates achieved in a wide range of building types.

In mechanically ventilated buildings, we can measure air delivery rates and the overall effectiveness of ventilation systems.

Specialities and test methods

  • Investigating ventilation failures and mould in housing.
  • Investigating ventilation behaviour by building users, including how often they open windows and doors.
  • Investigating effects of poor indoor air quality, including the effect of mould on lung function of building occupants.
  • Measuring building airtightness using a blower door.
  • Calculating background ventilation.
  • Directly measuring natural ventilation and infiltration rates using tracer gas methods.
  • Measuring performance of mechanical ventilation systems.