Treated timber ash

Treated timber is commonly used for pergolas, decking, cubby houses, claddings, posts, gates, animal enclosures, and landscaping timbers. Many of these structures may be destroyed or damaged during bushfires and the burnt ash may present a hazard.

Treated timber, if burnt, can produce an ash that may contain arsenic, chromium and copper. While arsenic is the most toxic, all three may present a hazard if ingested.


Inhalation would not normally result in poisoning in these situations.

Children, pets and farm animals should be kept away from land where treated timber ash is present.

Young children, especially those under 5 years, are at an increased risk from personal contact and ingestion.

This hazard is not normally encountered as the public is aware that treated timber should not be burned.

In domestic situations, small amounts of treated timber ash can be put in a sealed container and disposed in the garbage.

The ash and any remaining burnt timber in destroyed properties will be removed during the clean up operations.

Ash that may be a hazard in parks and public grounds will be collected during the clean up operations.

Personal protection when collecting ash

Do not touch the ash with your bare skin and avoid disturbing or spreading it.

Wear gloves while working with the ash.

Moisten the ash prior to handling with a shovel.

Remove and wash clothing. Clean footwear.

Wash your hands after finishing work and before eating or food preparation.

Health advice

The risk of poisoning from ingestion of treated timber ash is very low. If in doubt seek medical advice.