Dust Control – the dangers if not applied
Dust Control – the dangers posed by concrete dust in construction applications were largely ignored until recent years. In the United States of America, they were highlighted in some detail 50 years ago by an industrial hygienist called by Marion Trice. She was not the first one to recognise the problems.
Going back to 1700, Bernardino Ramazzini said dust that “dust would come to be proved fatal to stonecutters who took no precautions.
Dust is a term to describe minute particles with a diameter of fewer than 500 icons in diameter.
When it comes to demolition dust particles are much bigger in size. When it comes to occupational health, something we monitor very carefully throughout the Downwell Group, airborne dust particles are categorised in size by being either respirable or inhalable.
Respirable dust is small enough to be inhaled deep into the lungs; these are usually identified as particles under ten microns (PM-10). These tiny solids will penetrate far into the lungs and are almost certainly above the body’s natural cleaning mechanisms called cilia and mucous membranes.
In contrast, the larger dust particles in the inhalable dust classification are usually trapped in the nose, throat or upper respiratory tract. Human hair typically ranges from 50-75 microns in diameter, highlighting that the most hazardous dust particles are the ones too small to see.
There is a guidance sheet on dust in construction that can be accessed here
Dust Control during Demolition
In demolition and construction, there are generally three types of dust created, which are:
- Silica Dust – created from materials like concrete, mortar and sandstone.
- Wood dust – more common in construction methods
- General Dust – created from materials such as gypsum, limestone, marble and dolomite
All the categories can cause Lung Cancer, Silicosis, Chronic obstructive pulmonary disease or asthma
All our workers wear PPE that includes eye protection, and face masks (RPE) Face masks specifications are
- adequate for the amount and type of dust. RPE has a protection factor (APF) which shows the protection it gives the wearer. The level for construction dust is an APF of 20. This means the wearer will only breathe in a twentieth of the dust found in the air;
- suitable for the working environment – disposable masks can become uncomfortable to wear for long durations. Powered RPE helps reduce this.
- compatible with other items of protective equipment;
- fits the user. Face fit testing is needed for tight-fitting RPE
- to be worn correctly. anyone wearing a mask has to be clean-shaven
When it comes to the control of dust during operations, Downwell employs
- high-pressure dust bosses that project atomised water at and around the working area. With this method, groundwater is minimal
- dust sprays fitted to the long arms of the excavator
- water hoses
- scaffolding protection screens – covered in monarflex
This is supported by dust monitoring equipment that is positioned around the site boundaries and is in operation 24/7. If levels of dust rise above permitted HSE levels work will stop.