Health and Safety

Taking care with materials, equipment and work procedures and dealing with hazards.

Silica dust

Silica dust is produced when polishing and grinding concrete, and also when cutting concrete or masonry, or drilling, crushing and cutting some types of fibre-cement board. It can also be produced when cutting or grinding engineered kitchen benchtops that have a high silica content. Breathing in fine silica dust over prolonged periods can cause serious lung disease.

The disease is called silicosis, and there is a version called accelerated silicosis where symptoms can develop within 3–10 years of exposure to crystalline silica dust. This is serious – there have been deaths in Australia. In New Zealand, ACC launched the Accelerated Silicosis Assessment Pathway in September 2020. As of 1 August 2023, 190 claims had been lodged with ACC for assessment of accelerated silicosis.

It is common for people with this type of disease to not notice any symptoms in the early years, but anyone who has been exposed to silica dust for 6 months or more within the past 10 years should talk to their GP and lodge a claim to be assessed.

The New Zealand Carcinogens Survey, which covered 4,051 workers and whose findings were released in 2023, identified crystalline silica as a risk for builders: “Although efforts to reduce exposure to respirable crystalline silica have rightly been focused on the engineered stone-benchtop industry, the survey suggests that 44% of the construction industry are exposed to RCS.”

Protection required

Exposure to silica dust should be eliminated, isolated or minimised. Dust control is top priority:

  • Wet any dust before it can become airborne, and frequently clean work areas and equipment with water.
  • Never sweep up dry dust. Use a vacuum cleaner with a HEPA filter that takes particles out of the air.
  • When buying equipment for cutting and grinding, look for dust control features such as a dust collection device or a water system to the blade. Then make sure those operating the equipment use these features.

The appropriate masks should always be available. Where dust levels are low, disposable masks may be sufficient. Make sure they have two straps and fit securely around the face. Half-face or full-face masks will be required where dust levels are greater.

Make sure dusty clothes are cleaned and they do not carry dust into vehicles or homes.


Updated: 23 May 2024