How to check your office’s indoor environmental quality – an explainer


Ficus green leaves on the background ceiling air conditioner in modern office or at home. Indoor air quality concept

What is IEQ?

IEQ, or indoor environmental quality in your offices, refers to the quality of conditions experienced by the occupants of a building. It is determined by factors such as thermal comfort, ventilation, acoustics and layout.

The aim of understanding a building’s IEQ is to improve its inhabitants’ health and well being.

we spend around 90 per cent of our day to day lives indoors

It is an extremely important measure, considering we spend around 90 per cent of our day to day lives indoors.

What makes good IEQ?

Good IEQ is the result of how a building is designed, constructed and maintained. It also takes into consideration things like how the building is used and operated by occupants, and what chemicals and materials are circulated throughout.

At The Fifth Estate’s Happy Healthy Offices 19 event in Sydney in May, Adam Garnys, principal consultant at CETEC, pointed to a number of factors to consider good IEQ considers. 

They were:

  • Thermal comfort, such as the temperature, relative humidity, and air velocity
  • Indoor air quality, including particulate matter, airborne microbials, carbon monoxide, volatile organic compounds, or VOCs, such as those found in paints, and Formaldehyde
  • Ventilation effectiveness, such as the circulation or build up of carbon Dioxide
  • Lighting, including “horizontal task illuminance”, “vertical task illuminance”, and lighting uniformity
  • Acoustic comfort, including ambient sound levels
  • Office layout
  • Office cleanliness and maintenance

Basically, good IEQ follows a whole array of factors falling into balance within a building.

At a pragmatic level, it can lead to a number of positive outcomes. According to Mr Garnys, good IEQ in office buildings can lead to advantages such as increased productivity rates, reduced energy bills and staff costs, as well as credit points awarded by higher rankings in rating schemes.

In a more general sense, good IEQ leads to a building’s inhabitants being happier and healthier.

What leads to bad IEQ?

At the opposite end of the scale, poor IEQ can lead to a number of negative outcomes for a building’s inhabitants.

According to a report by the University of Melbourne, buildings with poor IEQ can cause people to experience very real and adverse “physical and psychological effects”.

Such adverse effects occurs when the environmental stimuli of a building, such as its sounds, smells, light and temperatures, are “beyond [a person’s] comfort thresholds for the activity they are undertaking”.

inhabitants’ health is affected by the quality of the building

This can lead to sick building syndrome, or SBS, where inhabitants’ health is affected by the quality of the building. These effects can include irritated eyes, nose and throat.

According to the report, “SBS is usually attributed to poor maintenance and operation of the building’s fresh air supply, material off-gassing, mould and inadequate ventilation of internal equipment (such as photocopiers)”.

The solution to SBS is often a focus on improved ventilation, but according to the report, this may end up “masking underlying issues with building materials”.

SBS and other negative effects of poor IEQ can have a “significant effect on staff productivity and absenteeism, affecting a business’s economic performance”.

One report by the Building Commission Victoria estimated SBS as a result of poor IEQ could cost the Australian economy $12 billion per year.

How do you measure it?

IEQ is often measured through occupant feedback, such as with the Building Occupants Survey System Australia, or BOSSA, devised by the University of Sydney’s IEQ lab.

It is a web based questionnaire designed to gauge the satisfaction of building occupants in order to assess IEQ performance. It does so by asking occupants to rate their overall experience with key IEQ dimensions such as spatial comfort, noise distraction and connection to the outdoors. 

BOSSA is considered the gold standard for occupant IEQ feedback, and so is endorsed by a number of highly regarded ratings systems such as the National Australian Built Environment Rating System, or NABERS, and the WELL Building Standard.

IEQ can also be measured by technology, such as with the University of Sydney’s SAMBA device. Also created by the university’s IEQ lab, the SAMBA is a small piece of hardware that can deliver real time insights into IEQ performance.

It measures aspects such as lighting, indoor air quality (such as carbon dioxide, carbon monoxide, particulate matter, formaldehyde levels, acoustics and thermal comfort (such as air temperature, radiant temperature, air speed and relative humidity). The SAMBA then offers up data such as a weekly report with which users can identify shortcomings and potentially improve a building’s IEQ.

How can you improve it?

Mr Garnys offered these five tips to improve a building’s IEQ:

  1. Air supply: ensure you have a good, intelligent supply air control that can be delivered when its needed, where it’s needed
  2. Have high ventilation rates: lots of studies show that this delivers better outcomes for occupants as long as filters are adequate and functioning appropriately
  3. Cleaning practices: you don’t think about it but every night when the cleaner comes around they are redistributing dust if not using the right vacuum cleaner with a HEPA (high-efficiency particulate air) filter
  4. Air handling units: you’d be surprised how air handling units can have a pool of water in them all the time, which can be problematic. Check that that the filters have been installed correctly
  5. Airtight buildings: If you have all the other issues sewn up, make sure you can control air into and out of your office to maximise the gains