Global = affects the entire atmosphere (for example, many greenhouse gas emissions and long lived air toxics).

Regional = affects whole regions or cities (for example, emissions from transport and domestic heating).

Local = affects just the immediate vicinity (for example, emissions from specific discharges, often large industrial plants or specific roadway intersections).

Ecosystems:

• Hazardous air pollutants will generally have similar effects on fauna as on humans.
• Particles can affect plants although there is little information available. In very dusty environments, particles may affect photosynthesis in plants by settling on leaves and reducing the amount of sunlight reaching the leaf.
• Sulphur dioxide can cause acid rain that seriously affects ecosystems. Acid rain is a major problem in the northern hemisphere, where trees and whole forests have been affected. Acid rain does not occur in New Zealand. However, sulphur dioxide deposition can affect vegetation around industrial discharges and in cities.
• Nitrogen dioxide is toxic to plants in short-term concentrations of 120 µg/m3 and reduces plant growth. When sulphur dioxide and ozone are also present, the effects on vegetation are worse. Along with sulphur dioxide, nitrogen dioxide can also cause acid rain.
• Ozone and other chemicals formed by photochemical reactions are toxic to plants in high concentrations. They can affect photosynthesis and plant respiration, reduce growth rates, and affect reproduction.

Air visibility

• Photochemical reactions in the atmosphere produce fine particles, such as sulphates, nitrates and organic aerosols in the air. These contaminants scatter light and can affect visibility.
• Fine particles in the air reduce visibility because they scatter or absorb light. This is usually associated with small particles or certain gases in the atmosphere and can occur at night or during the day.
• Sulphur dioxide can form secondary particles (sulphates) that cause haze and reduce visibility.
• Nitrogen dioxide can form secondary particles called nitrates that cause haze and reduce visibility (nitrogen dioxide is the gas that makes summer smog look brownish in colour).

Built structures

• Nitrogen dioxide forms acids in the presence of moisture and these can be corrosive to building materials at high concentrations.
• Ozone is corrosive to most materials at high concentrations, including plastics and metals.

Regional councils have responsibilities under s30 of the RMA for the control of discharges of contaminants to air.  Regional council responsibilities also include the strategic integration of infrastructure with land use (under s30(1)(gb)) and regional transport planning.

Territorial authorities have responsibilities under s31 to control the subdivision of land, and to achieve integrated management of the effects of the use, development or protection of land and associated natural and physical resources of the district. This includes effects on amenity values and effects of the land transport system. Territorial authorities also have responsibilities under the Health Act, but these are not relevant to district plan provisions.

The Resource Management (Energy and Climate Change) Amendment Act 2004 inserted "the effects of climate change" as a matter to be given particular regard to under s7 of the RMA.  The Amendment Act 2004 also specified the role of regional councils in respect of greenhouse gas emissions:

• S.70A requires that when making rules to control discharges to air "a regional council must not have regard to the effects of such a discharge on climate change, except to the extent that the use and development of renewable energy enables a reduction in the discharge into air of greenhouse gases…"  and
• When considering an application for a discharge permit or coastal permit relating to discharges of greenhouse gases, s.104E requires that "a consent authority must not have regard to the effects of such a discharge on climate change, except to the extent that the use and development of renewable energy enables a reduction in the discharge into air of greenhouse gases…"

The 14 standards are made up of:

• seven activity standards that ban various activities that discharge unacceptable quantities of dioxins and other toxics into the air
• five ambient air quality standards for carbon monoxide (CO), fine particles (PM10), nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (03)
• a design standard for new small-scale domestic wood-burning appliances
• a design standard for the collection and destruction of landfill gas at large landfills.