Indoor Environment Quality

Most service sector and other office employees spend more than 80% of their time indoors. Buildings, therefore need to cater to their occupants – both in terms of their health and their productivity.

Indoor Environment Quality (IEQ) which is also called Indoor Environmental Quality refers to the quality of the indoor environment within and around buildings and structures, especially as it relates to the health, comfort, and productivity of building occupants.

The recognised parameters of IEQ include:

  • Thermal Comfort

    • Temperature, Relative Humidity, and Air Velocity
  • Ventilation Effectiveness

    • Carbon Dioxide
  • Lighting

    • Horizontal Task Illuminance, Vertical Task Illuminance, Lighting Uniformity
  • Office Layout

  • Office Cleanliness and Maintenance


Many tools currently use a qualitative, “soft-science” approach to measuring these IEQ parameters and this often involves the use of simple satisfaction surveys. Whilst perception is important, in order to derive conclusions and provide solutions, a quantitative, rational and measurable approach is required in addition to sourcing occupant feedback.

Our scientific and technical approach to IEQ (which we have termed Facility Ecology™) makes us a national leader in this field. To date, we have conducted several hundred IEQ investigations. Whilst many of these have previously be conducted following problems with the indoor environment, many innovative clients are now using an IEQ based approach to maximise the productivity of their workspaces (Work Environment Productivity Assessments).

CETEC has been a long term and firm advocate of improving occupant’s satisfaction and wellbeing, corporate productivity, and facility efficiency through the development and use of the National Australian Built Environment Rating Scheme (NABERS) for Office Indoor Environment.

Environmental performance of a building is only one step in sustainability; the ability to deliver a high performing indoor environment which facilitates a healthy and productive workforce is an imperative sustainability driver for the property and construction industries.    

For more information about our related IEQ services:

CETEC has conducted thousands of indoor environmental quality assessments for companies, governments and organizations.

Due to our extensive knowledge and experience in indoor environment, CETEC was specifically appointed by the NSW Department of Environment and Climate Change in 2006 to develop the National Australian Built Environment Rating Scheme (NABERS) for Office Indoor Environment.  

In 2013, CETEC was selected onto a panel for the NABERS Indoor Environment Technical Working Group.  The updated NABERS IE tool was released in November 2015.

Some of our clients have included Brookfield, AMP Capital, ISPT, NSW State Property Authority, Local Government Super, Shape, Queensland Public Works, JLL, UNSW, NSW Attorney General. CETEC consultants are also technical advisors to the in-development Green Star Performance tool.

CETEC has long been at the forefront of knowledge of accurate and cost effective methodologies for Indoor Environment Quality / Indoor Environmental Quality (IEQ) assessment.

CETEC has also been actively involved with advancing and promoting the management of indoor air and indoor environment through:

  • Authorship of the Property Council of Australia manual for “Managing Indoor Air Quality” (1994) and also the new version “Managing Indoor Environment Quality” released at Green Cities 2009 in March.
  • Developing the National Australian Built Environment Rating Scheme (NABERS) for indoor environment in offices for the NSW Department of Environment and Climate Change (2006).
  • Chairmanship of the Australian Standards Indoor Air Committee.
  • Representation at Green Building Council of Australia Technical Committees for development of Green Star rating tools, including Green Star Performance. Independent Chairmanship of a Green Star Assessment Panel.
  • Delivering the “IAQ for Schools” report in 2003 for the Commonwealth Government Department of Environment and Heritage.
  • Three NABERS Accredited Assessors on staff.