National Environmental Standards - Air Quality (2011)

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What is the policy?

Living in clean, green New Zealand one deserves and expects a clean, healthy environment. This is not only for the people living on this planet today but also for the future generations to come. New Zealand’s national environmental standards have been introduced to allow everyone living in New Zealand to breath clean air, drink clean water and have clean land to live on. These standards have been issued under sections 43 and 44 of the RMA and apply nationally. Each and every regional, city or district council must enforce the same 14 standards in their regions. Seven standards ban activities that discharge significant quantities of dioxins and other toxics into the air, five standards are aimed at ambient air quality, one standard designed to enforce new wood burners installed in urban areas and the last standard a requirement for landfills over 1million tonnes of refuse to collect greenhouse gas emissions. The new ambient air quality came into force on the 1st of September 2005 and is said to be fully implemented by September 2013.

The Ministry for the Environment introduced the Ambient Air Quality Guidelines in 1994, this was revised and updated in 2004. These guidelines encourage the best ways to manage air quality strictly under the Resource Management Act 1991, and to also promote sustainable management of air resource in New Zealand (Thorton, D.P, 2007). There are guideline values which were suggested as being the minimum requirements that outdoor air quality should meet in order to protect the environment and also human health. If air pollution was greater than what the guideline values stated then emission reduction strategies were to be put in place to improve the air quality of that area. In the areas where levels did not breach the guideline values, efforts were made to maintain air quality and if possible reduce emissions. Under the RMA, Regional Councils are responsible for correctly managing discharged into the air and managing the quality of the outdoor air.

The Resource Management Amendment Act 2005 saw changes to the RMA as a result of dialogue with local government, industry, environmental organisations and the wider community over an 18-month period. The amendments enabled national environmental standards to be absolute and therefore not be over-ridden by rules or bylaws unless the standard states it may be over-ridden (Wickham, 2005).

The main purpose of the ambient air standards is to provide an assured level of protection for the health of all New Zealanders and accordingly they take out less strict local government controls. The standards also replaced any previous guideline levels and averaging periods, although guideline levels and averaging periods for pollutants are not covered by the standards still applied. The standards apply at any place in an airshed that is in the open air and where people are likely to be exposed to the contaminated air. Therefore, the standards apply in the open air wherever people may be exposed over the relevant time averaging period. This includes roadside verges, residential areas, central business districts, parks, beaches, etc. The standards do not apply indoors, in indoor workplace environments, in outdoor workplace environments where the public are not exposed, inside tunnels or inside vehicles (Thorton, D.P, 2007).

History of Air Quality

Air Quality and Pollution has been a long standing problem in New Zealand, particularly in southern and central areas. Christchurch in particular is one city which has had in the past, and continues to have problems with smog and air pollution. For this reason Christchurch provides a good city for evaluating how the air quality problem has changed, and how effective the various methods of management have been. It is important to note however that this issue is not unique to Christchurch: Twenty Seven urban areas experience particulate matter related poor air quality in winter months (Ministry for the Environment, 2011).

Christchurch’s air quality issues can be summarised by three main characteristics: The use of certain fuels in heating homes, the formation of the inversion layer due to the settled winter conditions, and the topography of the city (Appelhans, 2009). These factors interact to contribute to Christchurch historically having one of the worst records in terms of poor air quality (Spronken- Smith, Sturman and Wilton, 2002). With regards to the PM 10 standard however, Christchurch has made progress, particularly in recent years, improving air quality.

It was in 1972 that the first legislation was passed to control emissions. This took the form of the Clean Air Act and was the main form of air quality control law until the Resource Management Act (1991). The clean Air Act focused on domestic pollution and included regulations banning the installation of open fires. During the first half of the 20th century, the main issues of concern in air quality were Sulphur oxide, as well as PM10. Official Recordings of PM10 levels began in 1988, and were at this time already exceeding the council standard on almost 40 days of the year (Spronken- Smith, Sturman and Wilton, 2002). Even these high levels were a great reduction from previous levels.

The introduction of the RMA (1991), brought with it devolution of air quality control to Environment Canterbury, who developed an Air Plan, which was released in 1998. This plan contained a PM10 target of 50ug/m3 and methods of reduction mainly of restricted on log burner and fuel sources (Sproken- Smith, Sturman and Wilton, 2002). This plan also included subsidies to lower socio economic groups, for installing energy efficient heat sources. Despite this new management legislation the number of days in which the standard was exceeded continued to hold at similar levels throughout the 1990’s, accompanied by yearly fluctuations. In 1999 a study was conducted in Christchurch, investigating the sources of various pollutants, namely PM10 and CO2. This study attained that, in winter 83% of PM10 emissions were produced by domestic heating, while CO2 sources consisted of 52% from motor vehicles, and 47% domestic heating (Sproken- Smith, Sturman and Wilton, 2002).

The most recent form of legislation, the National Environmental Standards (2004), signalled a new shift again in air quality management in Christchurch and wider New Zealand. This Standard covered a variety of pollutants, including Sulphur Dioxide and Carbon Monoxide; however PM10 remained a primary focus (Ministry of The Environment, 30 September 2011). These cohesive standards, focused on air quality, wood burners, toxins and landfills (Ministry for the Environment, 30 September 2011). The impact that these standards have had, thus far has been vast, especially in Christchurch. In regards to the PM10 standard, in the years from 2001 to 2009 Christchurch has reduced its exceedences per year from, just under 60 in 2001 to fewer than 20 in 2009. This performance has been largely mirrored by Nelson, as well as other towns in New Zealand (Ministry for the Environment, 30 September 2011).

Although Christchurch’s story is only one example of air quality in New Zealand, its history, especially in regards to policy reflects, that of the country at large and provides a good demonstration of the air quality problem.

International Context

Introduction to International Standards

Air quality standards have been implemented globally in order to protect human health, the environment and the aesthetic qualities clean air provides (Thornton, 2007). Investigating the international context of air quality management is useful as it shows how New Zealand compares to the rest of the world in relation to air quality and the management of it. The world health organization has set some guidelines for particulate matter, ozone, nitrogen dioxide and sulphur dioxide, which are designed to offer guidance for governments about the health impacts of air pollution (World Health Organisation, 2006). These guidelines show targets for reducing air pollution to levels that the world health organization believes are best for human health (World Health Organisation, 2006). These targets are merely a guideline and countries are not required to comply with them. The guidelines are presented in table 1 below.

Table 1: WHO guidelines for specific pollutant levels


Methodologies used in different countries to manage air quality are often unique due to differing sources of pollution, attitudes, social, cultural, economic and political processes and ideas about air quality management (Thornton, 2007). This is emphasized in table 2 below which shows different countries and their regulations of PM10.

Table 2: International air quality standards for PM10


This table shows that different countries not only have different standards for Pm10 but also have differing numbers of exceedences allowed per year. Where New Zealand, Australia and the United Kingdom have the same standard, but exceedences allowed per year for each country are 1, 5 and 35 exceedences respectively.

This section will use three case studies of air quality management in the United Kingdom, Australia and China to show how air quality management occurs in these locations. Comparisons between these countries and New Zealand will then be made to show how New Zealand is addressing the issue of air quality within the global context.


Air pollution in china is one of the most visible environmental problems in rapidly developing china. A report published in November 2010 showed that a third of 113 cities surveyed failed to meet national standards last year. The World Bank stated that 16 of the worlds 20 cities with the worse air are in China. Only 1% of Chinas 60 million city dwellers breath air considered safe by European union standards (World Resources Institute 1999). China’s smog filled cities are concentrated with heavy industry, metal smelters and coal fired power plants. They may be critical to support their fast growing economy but are responsible for releasing tonnes of carbon, metals and gases into the air. The results are a large proportion of the population exposed to health risks such as chronic bronchitis, pulmonary heart disease and lung cancer.

Image: Smog in Beijing Aug 10 2007 Source:


Coal is the number one source of air pollution in China. China gets 80% of electricity and 70% total energy from coal with most of it being polluting high sulphur coal, although there are a total of nine pollutants that comprise the Chinese Air Quality Standards (Air Quality Monitoring and Forecasting in China 2009).

Table 3: Nine pollutants in Chinese Air

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The Chinese government has constituted laws in the field of ambient air protection, promulgated standards for air quality. The first air pollution law went into effect in 1987 and has been amended in 1995 and 2000. The 2000 amendments include several new requirements to enhance future air quality management. Including the endorsement of emission fees and permits (Air Quality Monitoring and Forecasting in China 2009). The State Environmental Protection Administration is responsible for national ambient air quality monitoring in China. The National Environmental Monitoring Centre is an institution directly affiliated with the administration and provides technical support, supervision and service for environmental management, plays a role as a network technical and training centre for national environmental monitoring and provides professional management and guidance for the national monitoring system. It is responsible for collecting, verifying and managing the environmental monitoring information and statistical data (Fang et al., 2003). There are more than 2000 environmental monitoring stations directly under government control, including state, provincial, city and county-level stations. Measurement methods range from chemiluminescence for nitrogen dioxide, UV fluorescence for sulphur dioxide and UV photometric for ozone, to gravimetric for PM10. A quality assurance and quality control programme exists to monitor the urban ambient air quality monitoring system (Thornton, 2007).

The Urban Branching Atmospheric Trajectory (UrBAT) model (Calori and Carmichael, 1999), is a three-dimensional multi-layered Lagrangian model capable of estimating ambient concentrations at urban scale (Thornton, 2007). The model is a modified version of the Atmospheric Transportation and Deposition (ATMOS) model (Heffter, 1983; Arndt et al.,1998) developed as part of the Regional Air Pollution Information and Simulation for Asia. Meteorological fields, terrain features, population density and emission sources were all incorporated as inputs into the UrBAT/ATMOS model, to generate spatial patterns of pollution dispersion and population exposure (Thornton, 2007).

To meet future challenges, the government needs to re-order its priorities and revise its overall development policy, so as to significantly improve the fit between development and environmental sustainability (World Bank, 2001). Market-based policy initiatives, such as coal price reform and emission levies, to adequately internalise the externality of the health costs associated with air pollutants is critical to support urban air quality management and improve population health (Chaoyang et al., 2002).

United Kingdom

Air pollution in the United Kingdom, (UK), is a problem which causes the approximate reduction in life expectancy of 7-8 months per person in Britain (Department for Environment, Food and Rural Affairs, 2007). The cost to the UK is not only the reduction in an individual’s lifespan but also the financial and economic costs associated with healthcare and loss of productive workers (Department for Environment, Food and Rural Affairs, 2007). Due to the detrimental effect of poor air quality, in 1997, the United Kingdom was the first country in Europe to develop an air quality strategy (Environmental Protection UK, 2011). This strategy has evolved over time with various amendments and has resulted in the latest strategy, the 2007 Air Quality Strategy for England, Scotland, Wales and Northern Ireland (Department for Environment Food and Rural Affairs, 2011).

This strategy argues that clean air is essential in people obtaining a good quality of life and is therefore very important that these standards are implemented to protect peoples health as well as the environment (Department for Environment, Food and Rural Affairs, 2007). Objectives and standards are used in this strategy, with the aim of reducing levels of nine pollutants (Department for Environment, Food and Rural Affairs , 2007). These nine pollutants are: Benzene, 1,3-Butadiene, polycyclic aromatic hydrocarbons (PAHS), carbon monoxide, lead, oxides of nitrogen, ozone, particles (PM10) and sulphur dioxide (Department for Environment, Food and Rural Affairs, 2007). A summary of these pollutants is shown below in table 4. These standards are legally binding and most of them are also subject to the Environment Act, 1995 (Environmental Protection UK, 2011).

Table 4: Nine main pollutants in the UK

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A key emphasis of the 2007 air quality strategy is local management of air quality (Thornton, 2007). This emphasis requires local government to assess air quality in their area and, through modeling, determine whether any of the 2007 air quality standards are likely to be breached (Environmental Protection UK, 2011). If modeling shows an area is likely to breach these standards an air quality management area, by law, must be declared (Thornton, 2007). Most predicted breaches are usually due to emissions from transport (Environmental Protection UK, 2011). Once the local authority has declared an air quality management area they must then create an action plan which describes how they will attempt to reduce pollution in that specific area (Environmental Protection UK, 2011). Despite this local authorities do not have to reach the objectives, as they do not have control over all the sources of the pollution (Environmental Protection UK, 2011). The 2007 air quality strategy also emphasizes that international cooperation and agreements are important as pollution is not constrained to each nations boundaries (Department for Environment, Food and Rural Affairs, 2007).

Image: Air Pollution in London August 2008. Source:


One method for improving air quality in England, which has recently been employed, is the launch of the Healthy Air campaign. It was launched in London on 5th July, 2011 with the aim of increasing public awareness about the impacts and effects of air pollution (Healthy Air Campaign, 2011). It aims to do this by encouraging communities to play a part in reducing air pollution through promoting active lifestyle choices (Healthy Air Campaign, 2011). As it is such a new initiative its effectiveness in increasing air quality is not yet apparent, however the idea of engaging the community in air quality issues is encouraging.


Recent studies have shown that Australians consistently rank air pollution as a major environmental concern.

Image: Air Pollution in Sydney 2009 Source:


On the 26th of June 1998 the National Environment Protection Council made Australia’s first National Ambient Air Quality Standards as part of the National Environment Protection Measure for Ambient Air Quality. The National Environment Protection Council is a statutory body within law making powers established under the National Environment Protection Council Act 1994 (Australian Government Department of Sustainability, Environment, Water, Population and Communities 2009). The Air Quality Standards were set for six pollutants to which Australians are most exposed.

Table 5: Six pollutants in Australian Air

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The 10 year goal of the Ambient Air Quality National Environment Protection Measure specifies that by 2008 the short term standards for carbon monoxide, nitrogen dioxide, ozone, sulphur dioxide and lead can only exceed 1 day, and for the particles (two size range) can only be exceeded 5 days (Australian Government Department of Sustainability, Environment, Water, Population and Communities 2009).

Table 6: Short term standards


This NEPM was revised in 2003 to include an advisory reporting standard for fine particles. Wiki7.png

To reduce Levels of the 6 major pollutants a range of national projects was implemented over 5 years though the $18 million Air pollution on major cities program funded through the National Heritage trust.

With the main sources of air pollution coming from transport and residential sectors the Australian Government has:

Set fuel standards under the fuel quality standards Act 2000 Phased out leaded petrol from January 2002 Tightened controls on emissions from diesel vehicles Introduced a new fuel consumption label for new car models Encourages the use of car pooling as well as bicycles for short journeys Alternative methods for heating, reducing smoke from woodheaters. Each state was required to develop and submit a plan specifying monitoring to be carried out for National Environmental protection Measure Purposes, according to requirements. With monitoring and reporting formally commencing in 2002, 79 urban sites monitored one or more of the 6 ambient air quality pollutants (Australian Air Quality Group 2011).

Monitoring is completed through The Tapered Element Oscillating Microbalance. It is a particulate material monitoring device which has a small pump that sucks air through a filter at a constant rate. The weight of the filter changes with more or less PM10 in the air, and this in turn changes the frequency of a small vibrating element in the machine. The TEOM calculates the amount of PM10 from the changed vibration. A high volume particulate sampler (HiVol) samples air by drawing it at a specified flow rate through a glass-fibre filter paper mounted beneath a protective hood to prevent material falling directly onto the paper. Each sample is weighed in a temperature and humidity controlled environment and the mass of the unexposed filter paper subtracted to determine the mass of sample collected (Thornton 2007).

Since reporting began, the standards to the extent specified are being met for all pollutants except particles and ozone. Adverse effects from the drought related dust storms and bush fires can lead to exceedences of the particles standards and can contribute to exceedences of ozone standards (Thornton, 2007).

International Standards compared to New Zealand

On an international scale New Zealand has some of the best air quality conditions in the world, especially when compared with countries like China or large urban cities located in the United kingdom and Australia.

Methodologies used to develop air quality standards are often unique to a particular country and are often more complex and established than that in New Zealand, where standards have been established based purely on health and environmental considerations, rather than the political, cultural or social issues many other countries have been in addition forced to consider (Thornton 2007).

The United Kingdom’s air quality management areas are largely influenced by traffic emissions as traffic emission sources count for over 95% of the United Kingdom’s air quality issues (Thornton 2007). This results in Air quality management areas in the United kingdom indicate the importance of transport and Land use.

Compared to China, the main sources of air pollution are fine particulate matter from coal combustion, such as soot, flying ashes and especially sulphate. Within the city area of Shijiazhuang, an industrial centre in north-east China with a population of more than 1.5 million, there are over 8100 coal fired boilers and industrial kilns, among which 30 are large point sources with high stacks over45 metres (Chaoyang et al., 2002). The emissions from such sources have played a prime role in shaping air pollution management in China.

The main sources of air pollution in Australia originate from the transport and residential sectors. This has driven a focus on monitoring and regulations for these sectors and the creation of the fuel quality standards Act 2000 which contained objectives such as the phasing out of leaded petrol by January 2002 and the encouragement of car pooling and bicycle use.

New Zealand’s local air quality management areas have been influenced with regard to our biggest air pollutants which come from the source of domestic heating from solid fuel burning and consider factors such as topography and meteorological conditions.

By examining air quality in the international context it is clear that New Zealand has air quality of a much higher standard than these other countries. The countries we have studied, like New Zealand have created standards and monitoring systems which have been put into place to deal with air quality issues. Due to different economic, political and social situations the methods employed and the standards formed may differ between countries, accounting for differences in air pollution sources and different views in air pollution.

Health impacts of poor air quality


Air pollution has a direct negative impact on human health, from subtle interactions with the respiratory system (asthma, shortness of breath) to the risk of hospitalisation and even death. Long-term exposure to high levels of fine particles increases the risk of heart and lung disease. In New Zealand, despite not having alot of heavy industry and a small population base, we don't escape the problem of air pollution and its consequent health effects. A number of urban areas, including rural towns like Masterton (Figure 1, above) or Alexandra, have air pollution problems, especially during the winter ( Air pollution has the potential to affect billions of humans worldwide and has been associated with developmental impairments, lung cancer and genetic damage to other tissues. (Somers, et al. 2004) The effect that seasons pose on mortality by respiratory causes is strong. With the majority of inversions + cold nights where people use their fires occurring in the winter months so too are the majority of deaths by repertory causes.

New Zealands third largest city, Christchurch is located in an area conducive of temperature inversion conditions in winter. Because of this any pollutants released during an inversion, including but not limited to PM10 pollution are trapped close to the ground until the inversion is broken when the sun heats up the surface in the early morning. The limit for ambient air quality guidelines in New Zealand is an annual level of PM10 of 20 μg/m3. Below is an image showing the average PM10 levels in all the major air sheds throughout New Zealand. Christchurch placed modestly with an average of 17μg/m3, however this is not to suggest that this area is void of times when concentrations are not high enough to cause adverse health effects.


Figure 2: Annual average PM10 levels compared to the annual guideline, 2010

Determining effects of individual pollutants is hard to do due to the high degree of correlation between them. A study undertaken by the Department of Public Health showed that in Christchurch an increase in PM10 of 10μg/m3 on the day prior to death of an individual was associated with a 1% increase in all-cause mortality and a 4% increase in repertory mortality. The association between mortality and air pollution is even stronger in people aged over 65. With a large proportion of elderly people in Christchurch there is real pressure to bring the number of exceedances down to a minimum.

PM10 is positively correlated with other pollutants such as sulphur dioxide which can be partly responsible for the mortality statistics. The adverse effects of air pollution may depend more upon the interactions of a mixture of chemicals than a dominant effect of a single pollutant such as PM10 and it may be more appropriate to view particulate level as a useful general indicator of air pollution.

Sulfur oxide pollution (as measured by sulfate particulates or sulfur dioxide) was notably associated with mortality from all other causes in addition to all-cause, cardiopulmonary, and lung cancer mortality. (Arden Pope III, 2002)

Air pollutants have had a worldwide effect on both wild mammals and wild birds often causing substantial decreases in local animal populations. The major effects of industrial air pollution on wildlife include direct mortality, disease, and physiological stress, debilitating industrial-related injury, anaemia, bioaccumulation, genetic mutation and die offs. (Newman, 1979)

There have been many reports of wide spread sickness and death of domestic animals attributable to industrial air pollutants. Episodes involving the sickness and death of domestic animals were reported as early as the 1870’s and have become increasingly frequent since then until the late 20th century when policy and science (in Europe and America) caught up with the harm that pollution was causing. Along with the greater environmental awareness that came in the late 1960’s so too was there an increase in the number of reported incidents of injury and death of wildlife from industrial air pollution. Reports of large die-offs of wildlife are uncommon. However in the early 1970’s sulphur emissions from a pulp mill in Canada combined with a heavy fog killed >500 songbirds. The birds exhibited inflammation of intestinal tracts and haemorrhages in the brain and trachea. (Newman, 1979)

Industry related debilitating diseases are the much more common. In 1969 arsenic emissions caused deer to lose balance and hair causing them to freeze to death in the northern hemisphere winter. “City living” of house sparrows Passer domesticus in California caused severe respiratory damage resulting in a population decline which still hasn’t recovered.

A number of pollutants have been found to concentrate in the tissues of wildlife. Fluoride has been found in high concentrations in the bones of rabbits and deer, hares, voles and sparrows. High fluroride has been found in the tissues of carnivores such as the barn owl and red fox. Cadmium levels four times higher than normal have been found in house sparrows in Japan and wild rabbits, ground squirrels and rats near a smelter in the US. Airborne mercury from a chlor-alkali plant in England has been found to concentrate in the tissues of several small mammals. Rabbits from areas of high sulphur dioxide and fly ash have a more acidic urine compared with rabbits from pollution free areas whereas nimals from areas with heavy cement dust have a more basic urine. Along with these unnerving statistics are changes in the age structure of these rabbit populations. In regions of high sulphur dioxide and fly ash the ratio of one-year old rabbits to adult rabbits is 30% below that observed in pollution free areas. In areas with heavy cement dust the ratio of one-year-old rabbits to adult rabbits is 35% greater than control areas.

The above mentioned effects might not directly result in death but often contribute to death during times of natural stress. Were population measurement have been taken, significant reductions in vertebrate wildlife have been correlated with industrial air pollution. The importance of industrial air pollution as a factor contributing to the decline in wildlife populations should not be underestimated.

In a study using lab mice in 2003 (Somers, et al. 2004). Two groups were randomly selected and exposed to ambient air for 10 weeks at two sites, one an urban-industrial area in Ontario, Canada and the other a control in a rural area 30km away. Comparison of germline mutation rates at DNA loci in mouse pedigrees from each site revealed a 1.5 – 2.0 fold increase on mutation rates at the urban-industrial site, providing evidence that air pollution can cause genetic damage in germ cells, inducing transgenerational effects.

The reason why this should be so alarming to all of us is if it can happen to animals and birds, then why not us? Also, a lot of these examples are from Europe or America where the populations are large so the consequences are also large and thus easily noticed. However, how developed does an industrial sector have to be before adverse effects occur but are not necessarily noticed? Probably not large at all. - Maybe these effects are there but are not noticeable, perhaps mutation of a few dozen base pairs from your genetic code per generation in a moderately polluted small town or a shortness of breath developing over years and eventually resulting in death at an old age. These consequences would certainly go unnoticed until the damage had already been done to several generations.


Figure 3:The true extent of damage we are doing to our atmosphere and ourselves may still not fully be understood.

Barriers to progress

The quantity of PM10 in the air is largely dependant on the amount of emissions given off by things like wood and coal fires, vehicles, and industry that reach the atmosphere. However, other factors such as local geography and weather also play large roles. Windy conditions allow pollution to disperse and consequently have a far smaller impact. On the other hand, features such as valleys and hills cause pollution to linger, combine and consequently intensify enhancing the effects. On top of this, during cold still conditions (generally through the winter months) temperature inversions occur that trap smog at street level beneath a layer of warmer air (figure 4). Therefore, at times pollution can be worse in a particular year because of the weather conditions alone, rather than as a result of increased rates of pollution. Conversely, a windy year with few temperature inversions may show fewer pollution episodes regardless of any changes in pollution emitted. This understanding though known is limited with no evidence on the relationship between the short term exceedances and the likelihood of long term exceedances (refer to section11). Accordingly, this lack of knowledge is a huge barrier to progress as it leads to limitations within the national standards.


Figure 4: Diagram illustrating the phenomenon of thermal inversion. (Source:

The highly subjective and reactive nature surrounding the resource consent process regarding emissions outlined in regulations 17-21 of the National Environmental Standards on Air Quality is also a huge barrier to the implementation of the standards. This is initially because it is stated that consents can not be granted to an applicant if any emissions are expected to significantly increase the ambient concentration of the particular airshed. As with the rest of the Resource Management Act (1991) this contains a dominant element of subjectiveness leading to inconsistencies and often lenient approaches to granting consents. For example, between 2005 and 2009 only three consents were declined on the basis of having emissions that may significantly increase that particular airshed's ambient concentration. On top of this, the standards only relate to consent applications that are made after the implementation date of September 2005. Consequently, unless stated in particular consents granted before this (through monitoring for example), these emissions are not likely to be changed. The interaction between these two factors represents what can easily be identified as an important flaw in the standards that have huge negative implications on the effectiveness of it being implemented.

Christchurch Case Study

The location of Christchurch city actually means it is predisposed to having air quality problems. The Port Hills (to the south-east of the city) act as a natural barrier that prevents the smog’s dispersal. In the winter months, smog becomes trapped down at the street level underneath a layer of warmer air (inversion layer). The climate of the area plays a part in the problem too. The average temperature in winter is just 12०C meaning most homes will end up using some form of heating. Wood burners are the cheapest way for most to heat their homes but are also the main cause of the city’s air quality problems. Burning wood (particularly moist wood) emits PM10 particulate into the atmosphere. Older fires, particularly those installed before 2000 (over 20,000 of which are still left in Christchurch), burn less efficiently emitting higher quantities of PM10. Eighty percent of Christchurch’s winter air pollution comes from wood or coal burners and open fires, while the remaining twenty percent is made up of vehicle emissions and industry (figure 5). Therefore the interaction of these above mentioned localised barriers give rise to the prominent issue Christchurch faces regarding their air quality.

The recent earthquakes the city has faced has proven to be a new barrier faced by authorities in controlling the problem. Since the September 2010 earthquake in the city the amount of PM10 particulate in the atmosphere has increased (the number of days exceeding national air quality standards this year is already double last year) due to the amount of dust and particulate thrown up by the event and its ensuing aftershocks. Wood and coal burning restrictions have been temporarily abandoned to allow citizens to heat their damaged homes. Control efforts will resume post recovery. Consequently, this is a large set back though one that the regional council can take limited action on. Realistically, authorities will have to aim to control the problem rather than eradicate it completely because of the complex interaction between all of these mentioned barriers.


Figure 5: Pie graph showing the percentage each factor contributes to the Christchurch air pollution problem.

How it is implemented

National environmental standards are mandatory technical environmental policies that have the force of regulation under the Resource Management Act 1991 (sections 43 and 44). Consequently they supersede any controls by local governments unless these are stricter than those prescribed in the national standards. In regard to the 2004 Regulations for Air Quality, these are to be implemented by regional councils and unitary authorities. The underlying obligation for these authorities is to control discharges to air so as to comply with the regulations set in the policy. This is primarily implemented through limitations and controls put upon resource consents that may have any adverse effects on local air quality. Within the policy are regulations that prescribe certain activities as prohibited such as Regulation 6.1 which states ‘the lighting of fires and the burning of waste at a landfill are prohibited’. On top of these prescribed criteria for implementation are underlying targets that are not accompanied with directive steps for their achievement. For example, the ambient air quality standards only explain the amount of times a standard can be breached without any suggested direction for reaching this, nor mentioning any specific activities that are prohibited regarding it. Therefore, due to this reactionary nature of the policy, (because it is largely influenced by the Resource Management Act 1991) depending on each region, the policy is generally implemented differently based on the particular problems and consents within a region. Therefore, in place of instructions, central government provides guidelines as to how councils may choose to monitor and meet the regulations mentioned in the policy. Additionally, deadlines are provided with the standards as to when regional councils and unitary authorities must meet particular targets for their airshed’s quality. Table 1 shows an example of these deadlines with only the critical ones shown. This is the central governments version of implementation which reflects their understanding of the specificity of the issue to individual qualities within each airshed.

Table 7: Summary of critical milestones arising from the Resource Management (National Environmental Standards for Air Quality) Regulations 2004 Table1.png

Therefore, implementation of the National Environmental Standards for Air Quality is not an entirely prescriptive process but generally a set of milestones that must be met by each regional council. An example of Canterbury’s implementation of the policy with regard to the city of Christchurch will examine in more depth as to how the policy is implemented at a regional scale.

Christchurch Case Study

Because of the widespread knowledge already grasped on the issue in Christchurch, all parties acknowledge that a significant problem exists. The majority of the debate on Christchurch’s air quality problem surrounds how the problem can be better managed. The major “stakeholder” and decision maker involved is the Christchurch City Council, who take responsibility for enforcing air quality standards and maintaining acceptable levels of pollutants in the city’s airshed. As mentioned, ultimate power is however held by national Government under their national air quality standards. The City Council’s management of the issue involved setting a goal of compliance with national air quality standards (not exceeding 50 microgrammes/m3 of PM10 per day) by 2013. This was done by zoning the city into categories of restricted use of wood and coal burning fires and zones with no restrictions, as well as rezoning some areas of industry. A full ban was imposed in some areas through the winter months to ensure milestones are met. This however did not remedy the problem, forcing the national Government to step in. They established the Clean Heat Project educating residents about cleaner heating alternatives and offering subsidies to people converting from open fires. ECan commissioner, David Bedford, was quoted as saying that the council’s energy activities were “largely redundant” now the government had a nationwide Clean Heat Scheme. Since 2003 the Clean Heat Project has seen 19,174 homes make the switch to cleaner heating. Though the Clean Heat Project was, and still is, a largely successful policy, the implementation problem in Christchurch remains.

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Figure 6: Map showing the division of Christchurch City into two “Clean Air Zones”. Homes in Clean Air Zone 1 face wood and coal burning restrictions while homes in Clean Air Zone 2 face no restrictions. (Source:

How New Zealand Air Quality is Monitored


Information For this section Was Taken from the 2011 Users’ Guide to the revised National Environmental Standards for Air Quality or from the web pages linked to the sentences eg. NIWA.

Regions within New Zealand are split into what is called an Airshed. Airsheds are regions that are designated based on distinct characteristics and point sources of pollution eg. Land Use and Industry. The Airsheds are then further broken down within themselves into sections, usually around urban centers called Zones. There are various types of monitors placed within the Airsheds that record information on various pollutants. Whether an area monitors a certain pollutant is determined by its likelihood of the area to exceed the national standards threshold for that pollutant. Other factors are monitored, like meteorological information such as wind speed, atmospheric stability, sunlight and temperature. Also,the effects of natural disasters, which might influence air quality negatively and skew the data are recorded. The data is averaged over the course of the year and, given that 75% of the data taken is not skewed or missing due to other factors, then the data is valid and counts for national air quality assessments. The Country also collates the data from all of the Airsheds together in a national network run by NIWA for a national assessment.

Figure 7: Map of Airsheds around New Zealand. Reproduced from the Ministry for the environment website


Monitoring Equipment

All Information about monitoring devices was taken from the Ministry For The Environment's Tech Report

Dioxin and Other Airborne Toxins

These pollutants are defined as airborne chemicals that may cause cancer or other negative health effects, or will negatively effect the ecology of the area. Some examples are benzene, perchlorethlyene, methylene chloride, dioxin, asbestos and heavy metals.

Lead is collected as particulate from the PM10 sample filters and tested for lead by using the gravimetric method. Lead is calculated in three month averages . Samples can also be collected from ß-attenuation sample and TEOM samples (see Pm10 methods below).

Carbon monoxide, Nitrogen Dioxide, ozone, Sulfur Dioxide

New Zealand participates in a global research project with the world health organization that monitors the above toxins on a global scale. The project is part of the Global Environmental Monitoring System or GEMS for short. In new Zealand there are three monitoring sites, one in Christchurch and two in Auckland.

Carbon Monoxide is measured using one of two methods, either non-dispersive infrared analyzers and electrochemical systems. With infrared analyzers the air sample is treated with broad band radiation and the amount of radiation absorbed by the carbon monoxide is compared to a reference beam . carbon monoxide is singled out in the air samples through a gas filter correlation. Water vapor is the main interfering gas in this test. This is the preferred method of sampling. Electrochemical analyzers diffuse the sample gas into an electrolyte, then oxidation or reduction by an electrode. What is measured is the current generated by the carbon monoxide. Other gasses may alter the measurements and so a filter is needed to get an accurate measurement.

Nitrogen Dioxide is measure in only one way in New Zealand and this is called continuous analyzer based on ozone chemiluminescence. Nitrogen Dioxide is first converted to nitric oxide by means of a reduction catalyst. Ozone is generated in the device and exposed to the Nitrogen oxide in the air sample. This reaction gives off light which is measured. The sample device then subtracts the amount of Nitrogen oxide from a measurement of total oxides of nitrogen that was made as the sample passed over the reduction catalyst. Measurements are recorded every six seconds and then averaged into one hour and twenty four hour hour measurements.

Ozone is measured in one of two ways in New Zealand ultraviolet photometry or ethylene chemiluminescence (the more common method). The air sample is hit with an ultraviolet wavelength of 254nm wavelength and some of this ultraviolet light will be absorbed by the ozone in the sample. The change in the amount of energy reaching a photomultiplier in the device will indirectly measure the amount of ozone in the sample. This method is common in calibrating ozone monitoring equipment as well as monitoring. Chemiluminescence exposes the sample to ethylene gas. Ozone react with the ethylene gas and gives off light at a wavelength of 430 nm. A photomultiplier measures this light.

Sulfur dioxide and Hydrogen Sulfide are measured using one of two systems, either wet chemical or instrumental means. The Wet chemical method works by a peroxide solution absorbing the Sulfur dioxide and then testing the pH of the solution to measure the extent of the absorption. It is not a true measure of sulfur dioxide, but a measure of the acidity of the air in general. The samples are taken over the course of 24 hours. One Instrumental means of measurement is the flame photometric detector. A flame with hydrogen ignites the particles and the flame gives off ultra violet light. A photomultiplier detects this light. Unless equipped with a particular filter, this method detects many sulfur compounds. Another instrumental method is the fluorescence detector which irradiates sulfur dioxides and then measures the unique wavelength that these irradiated particles give off. It is selective of sulfur dioxide and is considered better than the photometric detector in its practicality and its accuracy.


There are several methods currently being used to measure particulate matter in New Zealand. Most often, a High volume air sampler is used where air is drawn in at 1500 liters per minute through a 25cm by 20cm glass fiber filter The high volume air sampler has a special inlet that allows for the targeted size to come though. Each sample is taken over twenty four hours and each device has between one in six filters so that a weeks worth of data can be collected at once and added together to contribute to the yearly average that is used to monitor air quality locally and nationally.

Other methods include dichotomous air sampler which air is similar in that it draws particles into a mechanism with a selective inlet, but where it is different to the former is that it uses an impactor to separate the particles by size, fine (less than 2.5 μm) and coarse ( greater than 2.5 μm). The particles are collected by two filters that are weighed before and again afterwards to determine the amounts of particulates. The sampling is over twenty four hours.

The ß-attenuation tape sampler draws air into the device at 15 to 20 liters/min through a glass fiber or through Teflon tape. Particles called ß –particles are used to measure the build up of particulates based on changes to the amount of absorption. Measurements are taken over one hour and the tape is set to advance at the end of the hour or when the next measurement is set to take place to continue testing. The tapes are large enough to last for months of testing.

The tapered element oscillating Microbalance (TEOM) measures airborne particulates by drawing air through a filter that is attached to an oscillating microbalance. As the balance gathers particulates, its oscillation alters in a way that is directly proportional to the amount of particulates in the device and a computer records the data every five minutes. The unit operates continuously and the filter needs to be changed monthly or more depending on the particulate load in the machine and weather it has reached its capacity

The methods that best suit the testing for pm10 vary based on cost, practicality and the use of appropriate filters and inlets for the devices, as well as the general airflow at the site the unit is placed.

Environmental Effects

Low Concentration Issues

Air pollution, even in small concentrations, has the ability to cause severe damage to human health. In New Zealand, compared to many other countries, the concentrations of pollutants are relatively low. Due to the geographic isolation there is almost no trans-boundary flow of pollutants from other countries and the dispersion and the general low population of the country mean that pollutant concentrations stemming from local sources are also comparatively relatively low.

As mentioned, this does not mean that the deleterious effects on human health from pollutants is not an issue within the country. From research carried out by the World Health Organisation 2003 report "Health aspects of air pollution with particulate matter, ozone,and nitrogen dioxide" it is evidenced that for “cardiopulmonary mortality, and especially for lung cancer mortality, the risk was elevated even at (long-term) PM2.5 levels below 10 micro g/m3”. Stated also is the peculiarity that at these low concentrations, the exposure-response relationships of the above mentioned mortalities were evidenced at being in some cases greater than at higher concentrations. Although this evidence contains uncertainties due to some non-linearities of the relationships making it difficult to draw definite conclusions.

A brief aside to environmental impacts but with them still in mind; it is worth mentioning that, due to these findings showing that at very low levels of pollutant concentrations there can still be profound effects on human health, it raises the question of how effective national guidelines are. They are put in place to manage the nations health, but the population’s health will always be at risk if there is no proven threshold below which no effects are seen. And within a population there is always such a large range of susceptibility, owing to previous health conditions and age, among other factors, which can lead to illness. This non linearity of mortality in relation to pollutant concentrations means that often effects of low level concentrations can be underestimated while at the other end of the spectrum, where the relationship between the two flattens off, the effects of mortality can be over-estimated. The function of the guideline concentrations are to allow achievable and acceptable targets to keep health effects at a minimum. The thresholds must accept there is a range of susceptibilities within the population and be set accordingly. Unfortunately it is unrealistic to assume, due to this range in susceptibility, that in the near future there will be a guideline set that will accommodate the needs of all people, as this would in effect likely require national air quality standards to forbid almost all types and emissions.

Acid Deposition

Erzgebirge, Germany

Effects on the environment stemming from air pollution are wide reaching and have numerous and mostly negative effects. Effects include dry and wet deposition of acids on plants and forests, eutrophication, haze, effects on wild life, ozone depletion and climate change.

Acid deposition is one of the most obvious effects of particulate air pollution. Although not wide-spread in New Zealand, acid deposition, both wet, in the form of acid snow, hail, but predominantly rain, and dry, are large contributors across the globe to devastation of forests, especially boreal and temperate forests found in the higher latitudes across Europe and North America. With New Zealand also having largely temperate forest, parallels can be drawn as to predicted outcomes of potential devastation in a New Zealand setting by comparison with well researched and documented damage across northern hemisphere forests. The consequences of European outcomes can act as warning for New Zealand to the delicateness of forests and other eco systems to changes in air and soil chemistry Affected also are buildings and materials with which it can react. These effects are not just environmentally damaging but can often also carry with them large economic disadvantages, especially in cases of forestry and also implications of knock-on health effects to humans.

The relationship between suspended particulate matter and acid deposition is closely related as has been evidenced in many parts of Europe. Large proportions of sulfates are found in each and these are known to cause damage to ecosystems. The causes of these sulfates are from both primary and secondary sources, with primary sources being mostly sulfates from combusted fossil and bio fuels, while secondary sources occur when airborne particles oxidise sulphur dioxides, nitrogen dioxides, and aerosols. The effects on forests can be seen through thinning of the crowns of trees, the browning and decay of leaves and growth patterns which are affected by additions of sulphuric acid and nitrates to the soils which in turn lowers the pH. The additions to soils also cause leaching of heavy metals such as aluminium, nickel, cadmium and mercury. The mentioned heavy metals can be, by way of nutrient imbalances and uptake disturbances mainly from increased nitrate levels, absorbed through root systems into the trees and thus further impeding growth and raising the chance of mortality. Heavy metals not absorbed are washed away as run-off and end up in streams and lakes, having an influence upon the food chain. Of the many animals who consume those species living in affected water-bodies, humans are a large consumer and are greatly affected by way of the heavy metals stored in the tissue of fish (Johnson and Siccama, 1983). Research has shown that mass seasonal deaths of fish in particularly affected lakes and streams are the result of these effects. What can be seen here are not just the immediate effects of acid deposition by way of air pollution (in this case mainly just nitrates and sulfates), but also the knock-on effects which have various and wide reaching implications, many of which whose long term effects not known owing to lag times between cause and effect.

Ocean Acidification

Ocean acidification is one of the most concerning impacts of cumulative air pollution. Although the topic covered is largely based on particulate matter rather than gases, it is worth mentioning the role of carbon dioxide(CO2), which is also emitted from the sources documented such as wood burners, coal fired power stations and transportation and all affect air quality. Although CO2 concentrations are currently negligible in terms of direct effects on human health, long-term effects on humans from the implications of acidified oceans have worrying consequences.

Ocean acidification is carried out by the absorption of natural and anthropogenically emitted CO2 contained in the atmosphere into the surface waters of the oceans. Here there is a supersaturated concentration of calcium and carbonate ions which are crucial for oceanic calcifying organisms, such as molluscs, corals, echinoderms, foraminifera and calcareous algae, whose structural shells and skeletons are reliant on it’s presence to form them (The Royal Society, 2005). The addition of acidic H+ ions leads to a lowering of the pH which depletes carbonate ions and also weakens any existing structures formed. Although the carbonate ions act as a buffer in neutralising the formation of acids, the capacity of this buffer to function effectively is depleted through increased use. Unfortunately science has not shown an explanation for all functions of carbonate ions in the marine environment, but is proven to be integral to the biology of it’s species. This uncertainty shows that very high precaution should be exhibited in the form of a reduction to concentrations of CO2

Ocean pH

How effective have prevention efforts been?

The effectiveness of the national environmental standards addressing air quality has varied depending on the region and the barriers faced there. Based on the last environmental report card released in 2009, in 2007, annual compliance with the standard for PM10 has increased since 2005 from 31% to 42% of all monitored airsheds (figure 2). However, 18 of the 20 non-complying airsheds have continued to breach the standard within this period of time, a worrying sign to the effectiveness of the standard. Despite this, when considered as a long term trend all indicator zones in the five main centres of New Zealand met the annual guideline. Therefore it could be considered that although not always effective, (likely due to uncontrollable barriers mentioned such as geography and climate) the general trend is a positive one. Table 2 shows a more in depth long term trend of some monitored airsheds in New Zealand and their ability to meet the standards. This shows the extreme fluctuations that occur both daily and yearly representing the little impact this may have on the airsheds’ long term standards. There is currently not enough knowledge about the relationship between the daily maximum of an airshed and the likelihood of that region surpassing the national annual standard. For example, although the Otago region had the highest daily PM10 level and the most days of exceedance, it still met the yearly guidelines. Therefore it could be suggested that there are gaps in the research which is then reflected as gaps in the legislation. Although the majority of airsheds are improving in the long term, their compliance on shorter scales is suggesting that the standards may need to be improved or changed. A more in depth case study on the effectiveness of the standards in Christchurch will identify this along with the small scale issues that face the standards.

Table 8: 24hour average as 99.7%ile (PM10, ug/m3) (Source:



Figure 8: Summary of compliance with the PM10 standard in New Zealand

Christchurch Case Study

Despite the best efforts of local and national Government, the air quality problem in Christchurch remains. Though prevention methods implemented have reduced the severity of the problem through time (figure 3), PM10 levels in Christchurch are still bordering on hazardous. Earlier this year it was announced that Government appointed officials - who replaced elected councillors last May, plan to dismantle ECan’s clean air programme before its completion date of 2013. The nature of the legislation being enforced as standards without prescriptive measures to meet them allows for such phenomena to occur. Such disruption may not only undo the progress made but also lead to new barriers as well as the return of those that were already over come. This news came as national Government decided to relax national air quality standards, a reaction to the standards not effectively being reached. Therefore compliance with national air quality standards for Christchurch and a number of other smoggy towns has been pushed out to 2020.


Figure 9: Graph illustrating the improvements in the city’s air quality since 1990. Though average PM10 levels are trending downwards, current and daily levels are still bordering on dangerous. This chart does not include the dramatic negative effects of the recent earthquakes.


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