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The quality of air inside enclosed spaces is a matter of growing concern. Of particular interest are the subsequent health effects associated with exposure to pollutants found in the home environment and in non-industrial work places (e.g. schools, restaurants, public buildings, residential institutions and offices). Research has shown that indoor pollution concentrations can be significantly higher than outdoor ambient concentrations. Therefore control of the indoor environment (particularly the regulation of physical, biological and chemical pollutants) is an important factor for providing good, or at least satisfactory, conditions for human life. Individuals in industrialised nations spend between 71-96% of their time indoors. Therefore the indoor environment is important when evaluating pollutant exposures. In Australia, recent reviews of times spent in these environments show that people typically spend almost all of their daily time budget in enclosed environments (96% in 1997) and little time outdoors (4%) as indicated in the Time Budget table. As so much time is spent indoors, personal exposure to potentially hazardous air pollutants largely reflects indoor sources (see table). Indoor environments polluted by harmful substances may directly threaten health, shorten working lives, increase accident rates and reduce productivity. Some of the more publicised health effects result from exposure to asbestos dust (particularly during the renovation or maintenance of older industrial and commercial buildings) and pathogenic micro-organisms, such as the Legionella bacteria which is found in ventilation systems. Sick building syndrome has also received widespread attention but is much more subtle, and is unusual in that it is characterised by an increased prevalence of non-specific symptoms (e.g. irritation of the eyes, nose and lower airways). In recent years, knowledge in the field of indoor air quality has been increasing steadily in Australia. Reviews of both the non-industrial work environment and home, suggest that indoor pollutants are having a similar impact on the health of individuals as found overseas. Unfortunately it is difficult to get a clear and accurate picture of indoor air quality in Australia because, at present, there are no systematic monitoring programs. Overseas research has demonstrated that poor indoor air quality results in very high costs to a nation. Precise social costs are difficult to quantify because all estimates of population exposure to air pollutants have been based predominantly on data from outside air monitoring. Although outdoor contaminants influence indoor levels, they are not necessarily good indicators of the indoor environment. To add to the complexity, relationships between illnesses and exposure to pollutants tend to be overlooked, except when large groups of occupants within a building exhibit a recognisable pattern of symptoms such as that observed in sick building syndrome. Research has shown that 30% of the population can be expected to experience susceptibility to disease, worsening of existing disease, or sensitisation with or without other diseases because of indoor exposures. Health effects include allergy and effects on the immune system, cancer and effects on reproduction, respiratory effects and irritative effects on skin and mucous membranes of the eyes, nose and throat, sensory effects and effects on the nervous system and cardiovascular system. With such a range of potential health effects it can be assumed that the medical expenses (e.g. visits to the doctor, hospital care and surgery) associated with treating individuals (particularly patients suffering from allergenic diseases) would be considerable. In the USA, direct improvements in the indoor environment and a reduction of pollutants has been estimated to generate annual savings of US$6 billion to US$19 billion from reduced respiratory disease, and US$1 billion to US$4 billion in reduced sick building syndrome symptoms (Fisk and Rosenfeld 1997). Unfortunately, there are no equivalent Australian estimates. Summary of Australian studies examining building related illness in offices Study Occupants surveyed Building occupants with symptoms (%) Reported symptoms McKenna 1990 (Aust Capital Territory) 511 91% Too hot, drowsiness, headaches, sore throat Dingle and Olden 1992
44 65% Fatigue, sore throat, dry eyes Rowe and Wilke 1994
unknown 45% Too hot/cold, general symptoms Mesaros 1995
668 80% Fatigue, nausea, dizziness, sore throat Brown 1997
unknown 62-72% General symptoms, stuffy air Mesaros 1999
265 85% Fatigue, Stuffy nose, headache, eye irritation Source: Dingle and Olden 1992, Rowe and Wilke 1994, Mesaros 1995, Mesaros 1999 Indoor air quality issues are associated with the built environment. The region's climate, the density of buildings and the proximity to outdoor sources of pollution all affect indoor air quality. Outdoor sources of indoor air pollution and their characteristics Type or location of source General description or characteristics Climate/wind Weather conditions determine the amount of heating, cooling, and humidity treatment required for the outdoor air that is used for ventilation Outdoor air Outdoor air used for ventilation should be reasonably clean and not contaminated (e.g. pollens, heavy metals, inorganic and organic compounds). Outdoor air concentrations should not exceed relevant ambient air quality standards Adjacent and nearby sites Contaminants generated on adjacent sites may be a greater concern than regional ambient air quality. Sites to avoid are areas zoned for industrial use or sites that have the potential to contaminate building intake air e.g. near high traffic (carbon monoxide) Soil and groundwater quality Prior site uses may have contaminated the soil and groundwater. The most common contaminants are pesticides, herbicides and fertilisers (agricultural wastes), lead, solvents, arsenic, and asbestos (industrial waste) Noise and lighting Noise may affect the ability to use windows for ventilation or thermal control. Glare from adjacent buildings may influence the sizing and placement of windows Source: Maroni et al. 1995 One of the few Australian studies examining rates of sick building syndrome and geographical variations was conducted in Tasmania (Mesaros 1995). Results showed that sick building syndrome rates were highest within the Hobart CBD whereas outer suburbs (Clarence and Glenorchy) had a significantly lower percentage of building occupants experiencing discomfort. Assessing and measuring the current situation At present there is no systematic or routine monitoring of Tasmanian or Australian residential and non-industrial work indoor environments. Australian workplaces (industrial) and ambient air environments (e.g. various state policies and ambient air NEPM) have a range of regulations that require monitoring, but no regulations and monitoring programs have been developed specifically for indoor air (non-industrial workplace and residences). Australian indoor air quality strategies have been minimal and have tended to focus on state and territory government activities (i.e. a few reports reviewing the importance of indoor air), the development of interim guidelines, changes to national ventilation codes, improved building design and community education, rather than actual monitoring and data collection. The overall lack of data makes the development of state of environment indicators difficult. The lack of clearly defined responsibility for monitoring and setting standards for indoor air quality is a factor contributing to the lack of data in this area. Therefore, any new research would support the refinement and interpretation of the indicators included within this report (see Indicators section), and enhance the development of further indicators, such as the following:
Further discussion on these potential indicators is available through the link. |
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Occupant Satisfaction with Commercial Indoor Air Quality - at a glance If overseas research findings are any indication, the costs resulting from exposure to poor indoor environments are significant. The limited research in Australia indicates there is high occupant dissatisfaction with the commercial indoor environment. A study in Tasmania (Mesaros 1995 and 1999) revealed that between 80-85% of office workers in both pubic and private sector buildings experienced some type of dissatisfaction with the indoor air (e.g. factors associated with comfort and symptomatology). Further assessment of symptomatology and thermal comfort is important to help determine the extent of occupant dissatisfaction, and provide a basis on which to develop and implement any ameliorative and preventative strategies. |
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Mechanical Ventilation Rate of Commercial Buildings - at a glance Mechanical ventilation rates of commercial buildings have not been extensively investigated in Tasmania or in the rest of Australia. Therefore, it is difficult to determine the extent to which commercial buildings adhere to relevant standards. While buildings appear to meet the standards at construction, it is generally unknown whether they continue to meet those standards. The findings from a Tasmanian study (Mesaros 1995) indicated that the majority of low-rise buildings surveyed (in Hobart, Glenorchy and Clarence) did meet the mechanical ventilation standards, while those that did not also had a range of other indoor air quality problems. However, because no follow up study was undertaken, it is unclear whether the surveyed buildings still adhere to the relevant ventilation standards, and whether all buildings in the State are similar. |
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Thermal Comfort In Commercial Buildings - at a glance Thermal comfort variables (e.g. temperature, humidity, radiant heat and air velocity) have been shown to affect an occupant's health. However, the thermal comfort of commercial buildings has not been extensively investigated in Australia. Therefore, it is difficult to determine the extent to which commercial buildings adhere to relevant standards. The findings from the Tasmanian study (Mesaros 1999) show that some Hobart office buildings are relatively consistent in complying with thermal comfort standards. But, because no follow-up study was undertaken, it is unclear whether the surveyed buildings still adhere to the relevant thermal comfort standards, and if these results are indicative of all commercial buildings in Tasmania. Other studies (Mesaros 1997a, Mesaros 1997b) have shown there is variable compliance with recommended humidity levels within office buildings in Hobart. |
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Air Infiltration Rates of New Housing - at a glance The provision of adequate ventilation is important for good indoor air quality in residential houses. The exchange of air from the inside of buildings with outside air is important for ensuring there is not a build up of substances inside. However, air infiltration rates of residential buildings have not been extensively investigated in Tasmania or the rest of Australia, and there are no minimum air exchange rates required in Australian homes. Therefore, it is difficult to determine what proportion of Tasmanian houses have adequate infiltration rates. A past study found infiltration rates in unoccupied houses within Hobart to be at 0.55 air exchanges per hour (ACH) (Biggs et al. 1987), which meets the standard of several European countries (a minimum of 0.5 ACH). The current status of infiltration rates within Tasmanian houses is unknown due to the lack of recent research. This issue is particularly significant for Tasmanian dwellings because of the colder climate (homes are kept closed up for longer) and the high use of appliances that have the potential to introduce pollutants indoors (e.g. wood heaters). |
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Passive Smoking - at a glance Passive smoking involves the involuntary exposure to smoke, which can have detrimental affects on human health. The presence of smokers cause respirable suspended particulates to be three to twelve times higher indoors than outdoors. Data from the Healthy communities survey conducted by the Department of Health and Human Services in 1998 show that passive smoking is correlated to age. People aged 18-24 are the most likely to be exposed to passive smoking-often because of lifestyle activities. Younger groups reported significantly more exposure to tobacco smoke than older age groups. The survey found that most Tasmanian adults are not being exposed to passive smoking at home (72.5%), at work (67.2%), or in cars (68.7%). Passive smoking was reported to occur at social events (57%) and in other places (45.7%) (Department of Health and Human Services 1999). Research conducted in 1997 by the National Health and Medical Research Council (NHMRC) on passive smoking found that involuntary exposure to cigarette smoke increased the incidence of asthma in children, lower respiratory illness, lung cancer and major coronary events as well as a range of other illnesses. |
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Proportion of Commercial and Recreational Buildings with Smoking Prohibition - at a glance Even though the health effects associated with environmental tobacco smoke (ETS) exposure have been well documented, it remains clear that the proportion of commercial and recreational buildings with smoking prohibition has not been extensively investigated in Tasmania or the rest of Australia. It is known, however, that an increasing number of Australian buildings have applied smoking bans in the last 10-15 years. Tasmania enacted the Public Health Amendment (Smoke-free Areas) Act 2001 that banned smoking in many enclosed public places and workplaces, particularly building entrances and hotels where food is served. This followed the move several years ago to ban smoking in all State Government offices, buildings and vehicles. The Smoke Free Areas review - Report was released for public comment in 2003, which recommends the legislation be extended to require all bar and gaming areas, and 50% of outdoor eating to be smoke-free. Given the overwhelming evidence regarding the health effects of ETS exposure, any strategies addressing the control of ETS components are of great importance, especially in areas like public venues, where an individual has less control over their environment. |
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Proportion of Insulated Houses - at a glance Some types of insulation can cause a deterioration of indoor air quality. However, there have been few studies in Tasmania or Australia on wall and ceiling insulation within buildings. Therefore, it is difficult to determine the extent to which people are exposed to elevated concentrations of pollutants associated with insulated/uninsulated buildings. In Tasmania, 25% of homes are not insulated compared with 15% in Victoria and South Australia (ABS 1996). A lack of insulation can increase the rates of heating, potentially causing higher levels of outgassing of substances from building materials, which can affect human health. A Tasmanian study of office buildings found that hydrocarbon levels were twice as high in winter as in summer (Mesaros 1999). |
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Management and regulation of indoor environments in Australia are predominantly the responsibility of specific Federal and State government departments, with many having specific Acts pertaining to indoor (industrial/non-industrial) environments. The majority of State governments have adopted occupational exposure standards from other government bodies such as the National Occupational Health and Safety Commission. These government departments are not only responsible for the health and environmental regulations but may also undertake an advisory and public education role. The most recent Tasmanian action was the banning in 2001 of smoking in many public places, especially where food is being served. This followed the move several years ago to ban smoking in all State Government offices, buildings and vehicles.The Smoke Free Areas Review - Report was released for public comment in 2003. The report made a number of recommendations including that the current legislation be extended to require all bar and gaming areas to be smoke free to better protect workers and customers in those areas from exposure to the harmful effects of environmental smoke. It also recommended that 50% of outdoor dining areas be smoke free. The report followed a review of the Smoke Free Areas provisions of the Public Health Act 1997. Environmental protection authorities have probably been the most active (even though their approach is non-regulatory) in addressing indoor air issues. For example, the Victorian Environment Protection Authority undertook a review of indoor air quality in residential buildings even though their responsibility (under the State environment protection policy) is toward ambient outdoor air. The Australian Government's Living Cities-Air Toxics Program has progressed the recognition of indoor air quality issues. The air toxics strategy calls for the inclusion of indoor air quality in their program. Other departments such as the Australian Government Department of Health and Aged Care, (Queensland branch) have also been active in their approach to indoor air quality. In June 2000, the department released a report on the health impacts and management options of non-industrial indoor environments. This report was written by the Queensland Department of Public Works, Built Environment Research Unit (Building Division), and addressed the main issues associated with indoor air quality. Even though the activities in Australia have contributed to some much-needed information to the field of indoor air quality, their fragmented and independent approach make it difficult to assess the current state of air quality in a range of indoor environments in Australia. A comprehensive overview of existing information on indoor air quality and air toxics, however, has been published by Environment Australia: State of Knowledge Report: Air Toxics and Indoor Air Quality in Australia (Environment Australia 2001). The report is intended to provide a useful reference point for governments, industry and the public to develop appropriate management strategies.
In Australia, standards serve as guides only, and have no legal status unless they are specifically incorporated into Commonwealth, State or Territory legislation. The National Occupational Health and Safety Commission is recognised as the leading organization in developing national standards and codes of practice. However, most commission standards or guidelines are for industrial workplaces with few specific references to non-industrial workplaces, such as offices (NOHSC 3019:1994 - guidance note on passive smoking in the workplace, NOHSC: 9027571 - a guide on office copy machines, NOHSC: No 9027603 - guide on Legionnaires disease). Other government bodies such as the National Health and Medical Research Council (NHMRC) have gone further towards indoor air management by recommending indoor air standards and guidelines focused on non-industrial environments. Summary of NHMRC air quality goals for indoor air Pollutant Goal (at 0ºC, 101 kPa) Status Radon 200 Bq/m
3
(1 year) Final (action level) Formaldehyde 130 µg/m
3
(ceiling) Final (residences and schools) Lead 1.5 µg/m
3
(3 month) Interim Carbon monoxide 9 ppm (8 hr) Interim Nitrogen dioxide - Under review Total volatile organic compounds 500 µg/m
3
Level of concern Single volatile organic compounds 50% total volatile organic compounds Level of concern Sulphates 15 µg/m
3
Interim Sulphur dioxide 500 ppb (10 minute)
Interim Total suspended particulates 90 µg/m
3
(1 year) Interim Ozone 120 ppb (1 hour) Interim Source: NHMRC 1993 Guidelines and standards are a key element in controlling indoor air pollution, yet are limited in their application. They are at times not suitable or do not consider many factors e.g. low levels of contaminants, multi contaminant environments, private residences and public spaces such as shopping malls that are partially indoors and outdoors.
The best way to achieve good indoor air quality is source control. The NHMRC have recommended this approach and agree that this can only be achieved by regulating product emissions from building materials (NHMRC 1993). Australia uses a combination of standards and guidelines for the control of various pollutants and, to date, the only standard available for material emissions is for formaldehyde in building materials (AS1859 (1996) Part 1, reconstituted wood based panels: decorative overlayed wood, AS1859 (1997) Part 2, reconstituted wood based panels: particle board, AS1859 (1997) Part 3, reconstituted wood based panels: medium density fibre board).
The most recognisable code used in Australia is the Australian Building Code (ABC) (ABCB 1994). The Building Code covers issues like ventilation and fire escapes, but there is no mention of other areas of concern such as the type of materials to be used and placement of photocopiers in buildings such as offices. In some cases, codes covered by the ABC are clearly inadequate (i.e. no specifications for minimum ventilation rates in residential buildings), and require revision if improvements are to be made to indoor environments.
The Property Council of Australia, the Community Public Sector Union (CPSU) and Comcare have a program of accommodation issues, which is illustrated in a publication called Improving your work environment (1996) (PCA 1994, CPSU and Comcare 1994, CPSU 1996). It covers many non-industrial indoor air quality aspects including ventilation, pesticides, and hazardous chemicals, and is targeted at union health representatives. Local councils in all Australian States have no major function in controlling indoor air in non-industrial workplaces. Local councils merely reinforce the current Australian Building Code during and after completion of building works, with no subsequent follow up or monitoring of buildings.
The Asthma Foundation and the Heart Foundation are two organisations that have been active in drawing attention to the importance of managing the indoor environment. The Asthma Foundation published a brochure (Breathe easy not wheezy: home design) outlining the indoor sources of pollution (in homes), which are known to exacerbate asthma. Their focus was on sensible building design avoiding allergen-producing elements. The Heart Foundation has also placed a lot of emphasis on the dangers of environmental tobacco smoke in workplaces, homes and public places. This was mainly achieved through newsletters, seminars and television advertisements. Overall, education programs should be based on information from research that identifies potential problem areas, their causes and how to remedy them.
The only formal management actions in Tasmania that have taken place since the last SoE report has been the banning of smoking in many enclosed public spaces, especially where food is served. Generally, government departments and bodies only examine indoor environments (industrial/non-industrial) when a problem is drawn to their attention or when a management activity is required by legislation. For example, industrial hygienists from the Workplace Standards Authority (WSA) monitor industrial work environments only when an employer cites a specific problem. The Department of Health and Human Services generally have the same approach to their indoor air activities. A discussion paper reviewing Tasmanian ambient air quality standards (Ambient air national environmental protection measure (NEPM)) and policy (DPIWE 2000a), noted indoor air quality, but stated that any changes to policy will not apply to air inside buildings or where workplace standards take precedence. Regardless of this, the development of this air quality policy document offers an opportunity to formally recognise the possibility of problems and to establish a committee specialising in indoor air. Other groups and institutions such as Asthma Tasmania (DPIWE 2000b), the Tasmanian branch of the Australian Medical Association (Davis 2000), and the University of Tasmania (Todd 2000), have expressed their concern over indoor air quality in domestic and non-industrial workplaces. They highlight the need for indoor air quality research and management in Tasmania, following the release of recent research findings (Mesaros 1995, Mesaros 1999). The most significant development has been in the field of research. Two major studies on indoor air (non-industrial work environments) have been undertaken at University of Tasmania (Mesaros 1995, Mesaros 1999). This has contributed to some much needed information on the state of some Tasmanian indoor environments. The overall lack of indoor air quality management activities in Tasmania (Mesaros and Todd 2002) highlight the need for a comprehensive, quantitative assessment of Tasmanian buildings, as well as the development of suitable management activities. This review of indoor air pollution in Australia, and Tasmania in particular, has highlighted a number of key issues.
The Australian and New Zealand Environment Council (ANZEC 1990) produced a discussion paper on IAQ and concluded that the issue was not being addressed adequately in Australia, and recommended a strategy consisting of three broad approaches. These were:
Following the recommended strategies outlined by the council, it is clear that there is an overwhelming lack of information on indoor air quality (particularly non-industrial buildings). Therefore it is important for all Australian States, especially Tasmania (where indoor air issues have been largely neglected), to undertake more active strategies, like those seen in other Australian States (e.g. indoor air quality research in Victoria). Management actions in the next five years in Tasmania should be directed towards the following.
The key to controlling indoor air pollution is to prevent any future problems. The harmonisation of strategies outlined will be a step towards ensuring a safer indoor environment. In addition, any indoor air quality strategies implemented in Tasmania can serve as a model for other Australian States. Tasmania Together and the RMPS Relevant Tasmania Together goals and standards for 'Atmosphere' are listed in the linked file. The Tasmania Together Progress Board reported on progress toward targets for benchmarks set (Tasmania Together Progress Board 2003). Indicators, targets and baseline data are available in the latest Progress Report June 2003. Further information, including progress report updates, is available from Tasmania Together. Involvement of the community, and the fair and orderly use of resources are also fundamental principles of the RMPS. The RMPS objectives have been developed to advance the principles of sustainable development.
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