• What are the standards to achieve? (air standards and regional plan ambient air quality targets/goals may also include national ambient air quality guidelines).
• What data is available on:
  • air quality (pollutant monitoring)
• meteorology (meteorological monitoring)
• topography
• emissions (source, profile)
• dispersion characteristics
• population exposure (location, demographics, mortality and morbidity, health effects, costs)?
• What are the limitations of the data?
• What is the data showing us (current/historical trends)?
• Are there appropriate quality control mechanisms in place (ie, is the data validated)?
• Are there areas where good air quality is important, eg, National Parks or pristine areas, communities with vulnerable populations? This can help identify priorities for protection.

Rules that prohibit or require resource consent or specify standards may be used to deal with the effects of:

• some industrial or trade discharges
• home heating (in some regions)
• agrichemical use
• outdoor burning
• waste management
• intensive farming.

Section 15 of the RMA distinguishes between discharges from industrial and trade premises and other discharges.

Under s.15(1), any discharge of a contaminant into air from any industrial or trade premises is allowed only if it is expressly authorised by a rule in a plan, a resource consent, or by regulations.

The opposite presumption applies to discharges of contaminants into air from any other source under s.15(2): that is, unless there is a relevant rule in a plan, discharges of contaminants into air from sources other than industrial or trade premises can take place without a resource consent.

Therefore, without rules in a plan, discharges of contaminants into air from industrial or trade premises, no matter how minor, require resource consents, while possibly significant discharges from other sources do not. A key function of regional plan rules is allowing minor discharges into air from industrial and trade premises that are unlikely to have any significant adverse effects, and to regulate any other discharges that may have significant adverse effects. A catch-all rule can be used for industrial and trade premises that are not addressed elsewhere in a plan.  Such a rule should default to the discretionary activity category, to be consistent with the presumption under the RMA.  

Under s.2 of the RMA, the best practicable option (BPO) is defined as:

BPO, in relation to a discharge of a contaminant or an emission of noise, means the best method for preventing or minimising the adverse effects on the environment having regard, among other things, to—

(a) The nature of the discharge or emission and the sensitivity of the receiving environment to adverse effects; and

(b) The financial implications, and the effects on the environment, of that option when compared with other options; and

(c) The current state of technical knowledge and the likelihood that the option can be successfully applied.

The BPO can be used:

• where there is a lack of effects information
• where a precautionary approach is justified, or
• for issues such as odour where the effect is difficult to quantify and there are many contributing variables.

The BPO approach should only be used in defined circumstances, as defined in s.70(2) of the RMA, and should be used less often over time as more technical information becomes available.  The BPO approach can, however, be justified on an effects basis for certain technical approaches, and is therefore likely to continue to be used.  Plan changes should be considered when the BPO approach is no longer necessary.  

Regional councils and territorial authorities should consider using separation distances to manage effects that are largely qualitative in nature, such as odour, dust and spray drift.

Imposing building height restrictions in a defined area surrounding industrial activities with high stacks may be an appropriate method of managing the potential effects of exposure to pollution above ground level.  

Territorial authorities should consider both sensitivity and reverse sensitivity effects when considering where to locate new developments.  For example, a territorial authority may consider using activity status, buffer zones or separation distances to both protect new development from pollution and potentially polluting industry from unreasonable constraints imposed by new development.  

The main source of fine particle emissions in urban areas is solid fuel burning in home heating appliances.  

The air standards require all new wood burners in urban areas to have:

• an emission of less than 1.5 grams of particles per kilogramme of dry wood burnt, and
• a thermal efficiency of greater than 65 percent.

A reduction in fine particle concentrations and associated health impacts is expected as a result of the new design standard for wood burners.   However, it is likely that additional measures will be required in some airsheds to meet the particle standard by 2013.

Measures to reduce emissions from home heating might include:

• fuel/appliance bans/restrictions such as:
  • banning the use of open fires
  • banning the use of coal or wood
  • introducing more stringent emission limits than the design standard
• economic instruments including:
  • financial contributions/incentives for conversions to cleaner forms of heating
• education including promoting:
  • burning of dry wood
  • correct operation / maintenance of a burner
  • installation of low emission burners and pellet burners
  • appropriate choice of appliance size
  • energy efficiency measures
  • use of cleaner methods of home heating on high pollution nights
  • conversion to non-solid fuel burning heating devices.

An air quality monitoring strategy should:

• monitor the state of the environment
• monitor compliance with the air standards in accordance with the requirements of Regulation 15
• fill information gaps that have been discovered
• test assumptions implied by the plan provisions
• measure whether the plan is effective, by comparing actual results with the anticipated environmental results and measuring progress towards achieving the objectives
• monitor consent compliance and complaints
• monitor any delegations or transfer of powers.

Assessment criteria could include air emissions from new roads and the potential impact on the surrounding environment.

Urban design such as mixed used development that aims to reduce private vehicle use or the siting, orientation and design of roads and intersections that reduces air quality impacts.

This could involve developing planning approaches that promote land-use patterns that reduce dependency on private vehicles.