Minimising the emission of visible smoke from woodheaters and fireplaces can have substantial health benefits for the community in view of the harmful impacts of wood smoke.
The EPA recommends that councils consider the following options for tackling wood smoke issues in their local communities (councils may wish to adapt these suggestions to meet their own particular requirements):
- Community education programs
These programs can raise community awareness about the harmful impacts of wood smoke and the benefits of correct woodheater operation. A Council Resource Kit provides detailed guidance on running a community education program.
- Smoky chimney surveys
From time to time councils may carry out a local smoky chimney survey to identify chimneys that appear to be emitting excessive smoke. (Note: Excessive smoke is defined by the Protection of the Environment Operations Act 1997: see 1. Overview of legislative provisions for smoke abatement notices.) Householders may not be aware that their heater is smoking excessively and when given a brochure on correct woodheater operation it is likely that most householders will modify their practices in order to minimise smoke emissions.
- Smoke abatement notices
Where a householder has been given information on correct woodheater operation but makes little or no effort to prevent excessive emissions of wood smoke, authorised officers of local councils may consider issuing a smoke abatement notice. Information about smoke observation and issuing a smoke abatement notice is provided in Section 4. Preparing to issue smoke abatement notice.
Smoke abatement notice provisions were created primarily as a deterrent to poor woodheater operation. Accordingly, a warning about the smoke abatement notice provisions (given verbally or in writing) may provide sufficient incentive for the householder to improve the operation of their heater. EPA recommends that authorised officers of local councils intending to issue a smoke abatement notice should check that adequate information about correct woodheater operation has previously been provided to the household.
There may be circumstances where the requirements which would allow a smoke abatement notice to be issued have not been met (eg the plume length is less than 10 metres) or where an authorised officer of an appropriate regulatory authority (ARA) that is a local authority considers that a smoke abatement notice is not the most appropriate regulatory action. For example, the visible smoke plume from a chimney on residential premises may be less than 10 metres in length but causing significant nuisance to an adjacent residence. Or the local authority may wish the owner of a chimney emitting excessive smoke to adopt a particular solution, such as increasing the height of the flue. In these cases the ARA may consider issuing a prevention notice under section 96 of the Protection of the Environment Operations Act 1997 (see Section 2.2 Prevention Notices in Guide to Notices).
- Promoting better installation of woodheaters
Woodheaters are more likely to emit excessive smoke if they are incorrectly installed or poorly located within the home. Information on better installation is provided below under Promoting better installation of woodheaters.
Causes of excessive wood smoke
- Common operational causes of excessive smoke are:
- insufficient kindling
- too much firewood in the heater
- turning the air control to slow burn too soon after light-up or refuelling
- trying to burn a single large log
- adding firewood without opening the air control
- an incorrectly placed log which blocks the air supply to the base of the fire
- use of wood that is too wet
- Common installation or maintenance issues that cause excessive smoke are:
- heater flue is clogged with creosote and needs to be swept. Symptoms of a clogged flue are:
- the heater is difficult to start
- smoke enters the room when heater door is opened
- flue length is too short for adequate 'draw'. The flue is an important component of the woodheater installation and needs to be long enough to draw sufficient air for proper combustion of the fuel
- poor location of heater and/or flue. A woodheater will perform better (in terms of both heating effectiveness and reduced smoke emissions) when located towards the centre of the home and not against an outside wall
- DIY repairs such as those that leave the heater with missing components or the baffle plate incorrectly installed.
- heater flue is clogged with creosote and needs to be swept. Symptoms of a clogged flue are:
EPA's top tips for better woodheater operation
- Always burn small logs of aged, dry hardwood – unseasoned wood has more moisture and is more likely to smoke.
- Store firewood under cover in a dry ventilated area; freshly cut wood needs to be stored for 8–12 months.
- Never burn rubbish, driftwood or treated or painted wood. These pollute the air and can be poisonous.
- When lighting a cold heater use plenty of dry kindling to establish a good fire quickly.
- Stack wood loosely in the firebox so air can circulate – don't cram the firebox full.
- Turn off the warm air circulation fan when lighting up and when refuelling.
- Keep the flame lively and bright; your fire should only smoke for a few minutes when you first light it and when you add extra fuel. Open the air controls fully for 5 minutes before and 15–20 minutes after reloading.
- Don't let your heater smoulder overnight – keep enough air in the fire to maintain a flame.
- Check your chimney regularly – if there is smoke coming from the chimney, increase the air supply to your fire.
Clean the chimney every year, to prevent creosote build-up.
EPA recommends that each council develops a local woodheater installation policy incorporating measures to ensure that:
- all installations of new woodheaters comply with the requirements of relevant planning instruments(1) developed by Council
- woodheaters are installed in compliance with the Australian Building Code and Australian Standard AS/NZS 2918 to ensure the safety of the installation
- the woodheater is located within the home such that the flue system works most effectively – usually towards the central part of the home and not against an outside wall
- the flue is of adequate height(2)
- residents understand the requirements relating to the installation of woodheaters.
For further information on wood smoke issues the reader may wish to refer to the Wood-Smoke handbook: woodheaters, firewood and operator practice which was developed specifically to assist local government officers in identifying and dealing with wood smoke nuisance and broader scale wood smoke pollution.
Health impacts of wood smoke
During winter, smoke from domestic woodheaters causes substantial amounts of air pollution. Pollutants in the smoke include:
- gases such as carbon monoxide
- organic compounds, including air toxics
- fine particles, formed when unburnt gases cool as they go up the chimney; in the air, these can be seen as white smoke.
Who is at risk?
Wood smoke pollution affects everyone. It is harmful to the health of woodheater users and the health of others in the community. Health effects depend on the extent of a person's exposure to wood smoke, one's age and current state of wellbeing.
People who are more at risk are:
- infants and very young children
- those suffering from existing cardiac or respiratory conditions, such as asthma
- those with vascular complications from diabetes
- frail elderly people.
You can be affected by wood smoke:
- inside and outside your home
from your own woodheater or from other woodheaters in your neighbourhood.
Ways in which wood smoke can affect people's health
A poorly installed or leaking woodheater can cause excessive levels of carbon monoxide (CO) in the home. CO deprives the body of oxygen, impairing thinking and reflexes. At low levels of exposure, people can experience headaches, fatigue or chest pain; and at moderate levels, flu-like symptoms. At high concentrations, CO poisoning may result in death.
Particulate matter (PM) can cause short-term health problems including itchy or burning eyes, throat irritation and a runny nose, and illnesses like bronchitis. Particles can aggravate existing heart and lung conditions such as angina, chronic bronchitis, emphysema and asthma.
Air toxics generated during wood burning include polycyclic aromatic hydrocarbons (PAHs) which may cause cancer. Air toxics can also cause eye irritation, headaches and serious damage to the respiratory, nervous, reproductive, developmental and immune systems.
Studies have shown that PAH levels are highest during winter in NSW regional towns where woodheaters are a popular form of heating.
Smoky chimney surveys
Experience has shown that smoky chimney surveys by council officers can be an effective strategy to help improve the efficient operation of woodheaters across the community.
A smoky chimney survey may be carried out as follows (councils may wish to adapt these suggestions to meet their own particular requirements):
- Council officer(s) drives or walks along selected streets in the morning or in the afternoon looking for chimneys that are smoking significantly. The officer takes details of each address where a chimney is smoking significantly.
- After 10–20 minutes, the officer returns to the address and if the chimney is still smoking, records the details and stops to deliver a pamphlet in the letterbox. The pamphlet notes the time that the chimney was observed to be smoking significantly and provides hints on how to operate a woodheater correctly.
- Officer records the details of the actions they have taken, e.g. in a diary, notebook or other log for this purpose.
- As part of a round of inspections, the officer returns to the same address at a later date. If the chimney is found to be emitting excessive smoke, the officer tries to make contact with the householder, either on the spot or later by telephone, offering to arrange a visit to discuss the possible cause/s.
As a smoky chimney survey relies principally on the targeted education of householders, it provides a unique opportunity to improve woodheater operation without the use of a regulatory notice such as a smoke abatement notice. Nevertheless, the use of smoke abatement notices remain an option and thus underpins the integrity of the smoky chimney surveys as a realistic component of an enforcement scheme.
(1) Planning instruments can be developed by Council to ensure that woodheaters are only located in areas where there will be adequate dispersion of smoke from chimneys and that potential wood smoke nuisance to neighbouring properties is minimised. For example, Council may wish to prohibit the installation of woodheaters in sloping terrain where smoke from residences downhill is highly likely to impact on residences uphill. Council may also wish to consider the overall density of woodheater use with the local government area in order to determine whether some limitations on woodheater installation may need to be implemented to protect local air quality.
(2) Australian Standard AS/NZS 2918:2001 requires a minimum flue height of 4.6 metres above the floor on which the woodheater is located. To achieve the correct flue height, the flue kit must be at least 4 metres in length. Some installations may require even greater flue height to ensure adequate clearance above the roof or ridge line.
The above recommendations relating to woodheater location and flue height are important for ensuring that the flue system (a) creates sufficient 'draw' to enable the fire to burn effectively and (b) does not act as a funnel to allow cold air to enter the home when the heater is not being operated.