What is Silica & Silica Dust?

Silica is everywhere. It’s part of bricks, concrete and mortar. It’s in tiles and the slates on our roofs. It’s found naturally in stone and rocks. Even some fillers and plastic composite products use silica. Left alone, silica is safe. But if you work on materials that are made up of silica, you’ll be releasing dangerous silica dust. Activities such as concrete drilling, cutting, grinding, fettling, mixing, handling, dry shoveling and tunneling can all result in exposure.

The industries with the highest risk of exposure include construction, quarrying, mining, concrete manufacturing, brick & tile manufacturing, foundries, abrasive blasting, roading and monumental masonry work.

Silica dust is the very fine dust that’s created when you cut, drill, grind, chip or sand materials and products like stone, bricks, concrete, tiles or mortar.

Why is Silica Dust Dangerous?

Silica dust can be harmful if you breathe it in. Silica dust particles are much smaller than normal dust (sometimes invisible to the naked eye) – and they can get deep into your lungs and stay there, permanently damaging the lung tissue and eventually leading to serious lung diseases in some people. Silica dust can cause silicosis, lung cancer, chronic obstructive pulmonary disease (COPD) and kidney disease.

Eliminate the Exposure

Consider changing the product or process, for example use alternative products (eg metallic shot, slag products or grit for abrasive blasting, instead of sand).

Getting materials cut to size off-site in a facility where dust exposure can be controlled more easily.

Minimise the Exposure

Wet Working Suppression Methods

Use water to keep dust levels down. You need to use enough water for the whole time that the work is being done, not just wetting the material before you start as this does not work.

Dust Control Methods

Look for dust control features and dust collection systems when purchasing equipment and machinery. For example, tools used for cutting, grinding or polishing concrete and masonry should provide water to the blade and/or be fitted with on-tool dust extraction.

Ensure other dust generating equipment has a dust collection system with a filtered air supply to isolate the operator from the dust.

Use a ventilation system to suck the dust away before you can breathe it in. Some workstations have hoods or enclosures. Remove dust from work areas using vacuum cleaning systems with filters (HEPA filters).

Administrative Controls

Set exclusion zones which are clearly marked with signs that warn about the hazard and the correct PPE. You can also schedule any potential high exposure work for breaks or after normal working hours.

Personal Protective Equipment (PPE)

The PCBUs who direct the carrying out of work must provide PPE to workers however PPE is the least effective type of control measure and this should not be the first or only control measure that is considered.

Respirators

Wear a respirator that first correctly and is suitable for the job. The Respirator needs to meet the AS/NZS 1715:2009 standard. Seek expert advice when choosing PPE and ensure that information, training and instruction is provided to workers on correct use, wear, storage and maintenance of the PPE.

Carry out fit testing for each worker who will wear a respirator that requires a seal against the face. For further information, see WorkSafe’s fact sheet Respiratory Protective Equipment – Advice for Persons Conducting a Business or Undertaking.WorkSafe also has a helpful Respirator selection tool here.

TriEx can assist with qualitative respirator fit testing. To learn more please visit our website.

Protective clothing and cleanliness

It is important that you ensure your workers have overalls and gloves to wear at work.

You need to ensure facilities for washing are provided and that workers understand the importance of washing their hands before eating, drinking and smoking, and of washing up before they go home at the end of the day.

Exposure monitoring

As a PCBU you must, so far as is reasonably practicable, monitor workplace conditions if exposure to a particular health risk warrants it. Exposure monitoring will confirm whether workers are exposed to a substance at potentially harmful levels, and if existing control measures are working effectively.

Exposure monitoring should not replace the need for control measures to reduce exposure. TriEx can assist with arranging exposure monitoring at your workplace. Learn more here.

Health monitoring

In addition to monitoring conditions it is also a requirement that a PCBU must, so far as is reasonably practicable, monitor worker health if exposure to a particular health risk warrants it.

You must provide ongoing health monitoring for all your workers who may be exposed to silica dust. Monitoring must include lung function testing, and a respiratory questionnaire. TriEx can assist with arranging health monitoring by our occupational health nurses at your workplace or in one of our clinics.