Indoor Air Quality Standards Requirements

One of the most common questions asked when discussing indoor air quality (IAQ) is, “What is required by law in Australia. Although it would be short-sighted to see such minimum requirements as all that is needed to address the complicated IAQ issue, those responsible for maintaining buildings should at least be aware of these basics.

This document attempts to give an overview of the standards, regulations and legislation pertinent to IAQ in Australia at the present time. Of course it should be stressed that this is a rapidly evolving field and it is advisable to seek expert legal advice about your particular circumstances. This document does not purport to offer legal advice but rather outlines common requirements that property owners and managers should comply with as a minimum.

AS/NZS 3666-2002 Air handling and water systems of buildings – Microbial control

Part 1 Design, installation and commissioning

Part 2 Operation and maintenance

AS/NZS 3666-2000

Part 3 Performance based maintenance of

cooling water systems

Handbook HB32 Control of microbial growth in air-handling and water systems in buildings

Compliance with this standard is required by law for all buildings in most States. Although it was originally concerned mainly with the control of Legionnaires’ Disease, it now deals extensively with all forms of microbial control in building air handling systems as well as water systems. The Standard requires regular inspection of various components of the air-conditioning systems as outlined on the following table. These components must also be cleaned “when necessary”.

Component of AC System	Inspection Interval
Humidifiers	Monthly
Evaporative coolers	Quarterly when in use
Coils	Monthly
Trays and sumps	Monthly
Condensate drains, tundishes and traps	Checked monthly and flushed clean
Ductwork	Annually in the vicinity of moisture-producing equipment and selected access points
Fans and fan coil units	Annually
Terminal units	Annually
Cooling water systems (eg: cooling towers)	Monthly (cleaned every six months)