Silica (Silicon dioxide) is found in stone, rocks and sand and is also a major component of many construction materials including concrete, bricks, tiles, and mortar. When it is freshly ‘fractured’ through processes such as stonecutting, drilling, and polishing, it creates a fine enough dust to reach deep inside the lungs when inhaled. As RCS particles are invisible to the naked eye, high concentrations can be inhaled without the worker being aware of it.
Silicosis
An estimated 600,000 UK workers are being needlessly put at risk of developing silicosis – a progressive respiratory condition that can lead to death through being exposed to respirable crystalline silica (RCS). The majority of these are construction workers.
However, silicosis is an ‘entirely preventable’ [1] disease and by implementing a series of risk reduction strategies (including monitoring dust levels, taking steps to reduce exposure to RCS, educating workers about the risks of RCS and providing high quality RPE) employers can keep their workers safe.
In doing so, they will also save themselves and the wider UK economy millions of pounds. Indeed, while cases of occupational silicosis are under reported, and so it is hard to gauge the full cost to companies due to staff absence, individuals with silicosis have been awarded damages of up to £3.5m. [2]
At risk industries
Workers in the below industries are particularly at risk:
- Construction and demolition
- Mining and quarrying
- Pottery and glass manufacturing
- Stone masonry and stone cutting
- Worktop manufacturing and fitting
- Sand blasting
Implementing a hierarchy of control
According to UK regulations employers must:
- Carry out a risk assessment.
- Keep a record of the assessment (if they employ more than five people)
- Where practicable, consider substituting material with a lower RCS content.
- Prevent or control exposure to RCS.
- Explain the risks of RCS and how to avoid them.
- Provide the worker with respiratory protective equipment.
The role of PPE
In many instances, risks cannot be controlled by engineering controls alone and business’s need to provide their staff with high quality PPE.
Furthermore, staff should be properly trained to use to use, check and clean the RPE. There should be systems in place to make sure that disposable respirators are changed regularly, the filters on reusable RPE respirators are changed in accordance with manufacturer’s recommendations and the equipment is stored in a clean, dust-free place. Staff should also be empowered to report any problems (such as defective, old, or badly fitting RPE) to their supervisor.
When choosing RPE it is very important to remember not only to use masks that have a high filtration efficiency, such as an FFP3 Respirator, but also to make sure that the mask fits properly.
Fit testing for tight fitting RPE is the process of checking the seal between the mask and the wearer's face to ensure that the mask is properly fitted and able to provide effective protection against airborne particles. The purpose of fit testing is to identify any gaps or leaks between the mask and the face that could allow dust to enter the wearer's respiratory system.
It is important to note that face fit testing should be performed by a trained professional during the initial selection process of tight fitting RPE, it also needs to be repeated if there are changes to the wearer's face, such as weight loss or gain, or if the mask model or size is changed. Regular fit testing is also recommended to ensure that the tight fitting RPE continues to provide adequate protection over time, the recommended time is to re-test every 2 years which is recommended by the BSIF in the Fit2Fit Companions. HSE also outline further guidance & information when to re-test in the INDG479, Fit Testing Guidance Notes.
[1] 0 C. C. Leung, I. T. S. Yu and W. Chen Silicosis The Lancet 379:9830 (2012) p2008–2018 Available at: https://www.sciencedirect.com/science/article/pii/S0140673612602359