Indoor air quality

2011

Whereas Australia has had national standards and goals set for key pollutants in outdoor (i.e. ambient) air, there are no standards or guidelines for pollutant levels in indoor air. There are regulations and codes that address indoor air quality, but (with the exception of regulations dealing with gas heating appliances) these apply to workplaces and to commercial premises and public buildings, rather than to residential dwellings.152 Despite these limitations, Australian governments have actively sought to improve indoor air quality through a range of interventions (both regulatory and nonregulatory) targeting environmental tobacco smoke and unflued gas heaters.

In the case of environmental tobacco smoke (also known as passive smoking), powers to control smoking in public places lie mostly with state and territory governments. All states and territories prohibit smoking in cinemas and theatres (originally motivated by concern over risk of fire), in most types of public transport and in areas where food is prepared. Over the past decade or so, most jurisdictions have extended such prohibitions to cover cars carrying children and a wide variety of public places, including government buildings, airports, premises where food is consumed, pubs and nightclubs, and shopping centres. Increasingly, similar bans are being applied to various outdoor public spaces. States and territories have also used occupational health and safety legislation to require smoke-free work environments.198

As noted in Section 3.2.3, there is concern about the impact of unflued gas heaters on indoor air quality and therefore health. Although these heaters are primarily known as a source of nitrogen dioxide, they also produce carbon monoxide and formaldehyde. Unflued gas heaters are regulated in all states and territories. Although the regulations vary between jurisdictions, they all require compliance with Australian standards AS 4553-2000 (AG 103-2000): Gas space heating appliances, and AS 5601-2002 (AG 601-2002): Gas installations.199 However, as various studies have shown, conformity with the Australian standards does not guarantee that levels of nitrogen dioxide will not adversely affect health.167-168

In New South Wales, longstanding public concern over the use of unflued low-NOx gas heaters in schools led the government to commission a major independent review of respiratory health effects on children exposed to such heaters. The review, by the Woolcock Institute of Medical Research, found that, although exposure to these heaters was not linked to significant reductions in lung function, it did cause an increase in respiratory symptoms, especially in children with a predisposition towards developing allergic reactions. The review concluded that ‘it is important to seek alternative sources of heating that do not have adverse effects on health’.200 In response, the New South Wales Minister for Education and Training announced in July 2010 that the use of unflued heaters would be phased out in all New South Wales public schools.201

Box 3.13 Tasmania's planned burning issue

A key pressure on air quality in Tasmania is smoke emissions from planned (prescribed) burning that can impact on human health, amenity, tourism and viticulture. Most of the concern surrounds burning by the forestry industry in autumn, although other sectors contribute both in autumn and at other times of the year.

According to National Pollutant Inventory (NPI) data, smoke from planned burning contributes only 3% of total particle emissions in Tasmania.d However, a recent review indicates that the NPI methodology for estimating planned burn emissions is seriously deficient.159 It is now estimated that smoke from planned burning is responsible for approximately 50–80% of total particle emissions in Tasmania (the proportion varies from year to year, depending on the level of burning undertaken).196

Tasmania’s Forest Practices Authority, in consultation with the Environment Protection Authority (EPA), has established the Coordinated Smoke Management System (CSMS).e The CSMS provides for the coordination of planned burns to minimise the risk of high smoke levels in individual airsheds. It restricts the number of burns on days when weather forecasts and modelling predict poor smoke dispersal. Participation is voluntary and is currently limited to major forestry operators and the Parks and Wildlife Service.

To facilitate the assessment of the effectiveness of the CSMS and to provide real-time air quality data that can be fed into the CSMS decision-making process, the BLANkET (Base-Line Air Network of EPA Tasmania) smoke-monitoring network has been established by the EPA. BLANkET consists of a network of 17 indicative air quality monitoring stations (Figure A). Stations are located in regions away from the major centres of Launceston and Hobart, but in areas near where the forest industry and other sectors conduct planned burns.

Each BLANkET station consists of a low-cost optical particle counter that measures PM2.5 and PM10, a meteorological station and a communications link. Real-time data are displayed on the EPA Division’s website.f Performance of the stations has been very good, and there is high correlation between data from BLANkET and from reference low-volume air samplers at National Environment Protection Measure (NEPM) monitoring stations. The indicative data collected from the BLANkET network show that daily average particle levels above the NEPM PM10 standard and the NEPM PM2.5 reporting standard are sometimes measured in communities close to planned burn events.

The technology developed for the BLANkET network could also be used to facilitate the determination of population exposure to PM2.5 and PM10. For Tasmania, this approach is likely to provide a more realistic estimate of population exposure than inventory development and modelling, and at a lower cost.

Source: Tasmania Department of Primary Industries, Parks, Water and Environment (EPA Division)197

(2011). Ambient air quality: Indoor air quality. In: Australia state of the environment 2011, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/theme/ambient-air-quality/topic/indoor-air-quality-0, DOI 10.4226/94/58b65c70bc372