Grinding Dust and Wash Water in the Top End in Darwin

What grinding dust and wash water in Darwin actually involves

NT WorkSafe's bulletin is written for business owners and managers. It says that when workers cut, grind and drill these products under dry conditions, tiny particles of respirable crystalline silica dust can be released into the air. We do not restate its exposure standard, which is an employer's duty. For you, the question is how the dust will be controlled on your floor, and that is for the contractor to answer.

Slurry and wash water

The NT EPA's building-site guidelines (November 2015) say it is illegal to allow soil, cement slurry, paint, plaster or other building related waste materials to enter the stormwater system, and that on-the-spot fines may apply. They also say paint waste and wash waters must not be discharged into it, and that such pollutants ultimately end up in natural waterways, such as Darwin Harbour.

Before grinding starts

Ask whether the floor will be ground dry or with water, how dust will be controlled, where slurry and rinse water will be collected, and where it will be taken afterwards. If the house is older, the asbestos question comes first: see the older homes page.

The guidelines name Darwin Harbour as one of the waterways such pollutants end up in. The line is about the stormwater system, which any suburb on this site has, so a wash-down route is worth asking about wherever the floor is.

Grinding Dust and Wash Water in the Top End in Darwin — common questions

Is dry grinding a dust risk?

NT WorkSafe says cutting, grinding and drilling concretes under dry conditions can release respirable crystalline silica dust into the air.

Where may the slurry go?

Not into the stormwater system. The NT EPA says it is illegal to allow cement slurry, paint and other building related waste materials to enter it, and that wash waters must not be discharged into it.

Why does Darwin Harbour come into it?

The NT EPA's guidelines say pollutants that enter the stormwater system ultimately end up in natural waterways, such as Darwin Harbour.