The Dangers of Dust in Construction from Cement and Concrete
Silica – The hidden danger in Cement and Concrete
We often do not think about the abundant and commonly-used mineral, silica. It is used all over the building trades, especially in cement/concrete, in mortars, and in plasterboards.
When you cut, pulverize or grind silica –containing mixtures, they give off dust containing respirable crystalline silica (RCS). This is associated with the respiratory disease of silicosis.
Exposure to RCS gives rise to workers being at risk of developing silicosis and the disease makes breathing more difficult, increasing the risk of lung infection. Silicosis usually follows many years of exposure to RCS, which can be the case with long-serving building workers.
Very high rates of exposure suffered over a few months or years can give rise to acute silicosis, which can result in death within months of the exposure. Heavy and prolonged exposure to RCS under the same conditions that produce silicosis can also cause lung cancer.
Another possible outcome is the contracting of chronic obstructive pulmonary disease (COPD), which prevents you from breathing properly. This term includes chronic bronchitis and emphysema.
How can you avert these risks?
Essentially by damping down or sucking up the dust at source, and by personal protective equipment (PPE) for workers.
Methods of dust control, according to the equipment in use, include:
Suppression via -
- fog sprays
Collection/Containment via –
- bag fittings
By their very nature many construction activities have the potential to create dust. The control measures that you put in place should prevent dust from reaching levels that will cause harm to workers. On any reasonably-sized building site it is preferable to bring in ready-mixed cement rather than mix it from bags on site.
You must identify dust hazards within your risk assessments and then follow through with measures that work but do not unduly hamper your workforce: if the measures are too tricky to be easily applied they may be skipped, and if the PPE is too bulky or impedes vision then it may not be worn. If you lack the necessary expertise in this area then make sure that you call on the hands-on support of qualified Health and Safety Consultants such as McCormack Benson Health & Safety that have an extensive construction safety track record.
Such safety consultants will be able to carry out the measurements that will monitor exposure and assess how effective they are.
Having put a safety regime in place, it is also essential that you maintain and clean the equipment, especially dust-extraction motors and filters that can easily become blocked and ineffective. And do the people doing the job know what the permitted exposure levels are?
Dust caused by hand drilling of concrete can be controlled by drilling holes wet. Hand-held powered saws used for cutting concrete, asphalt and stone will also create large quantities of dust. They should not be used to cut dry. Where possible use a water-supplied cutting table, ensure that the water supply is maintained and always enforce the use of approved full face masks with breathing apparatus.
All trucks, forklifts, diggers, backloaders and other mobile plant create dust as they move around and during loading. Vehicle cabs should be fitted with filters appropriate to the risk created by the dust. Regular maintenance of the systems is essential and the cabs need cleaning regularly using vacuums.
Control and rest rooms need to be kept clean and have clean air at a positive pressure. Their seating should be capable of being cleaned, and this should be done regularly, to prevent build up of dust from overalls.
Areas of spillage such as around unbagging for cement mixers should be kept clean and vacuumed regularly. Never use a brush as it liberates dust into the air.
For more information on how McCormack Benson Health and Safety can help you combat the problems of Silica, please get in touch.