− providing workers with access to an area to wash their arms , hands , faces and hair − a low-pressure hose or tray of water may also be useful for cleaning the bottom of footwear to prevent tracking dust into other areas
− providing a laundry service for dusty work clothes and PPE so they are not taken home for washing o if a commercial laundry is used , dampen the clothes and place them in a sealed , labelled plastic bag , and inform the laundry that the clothes are contaminated with crystalline silica
− requiring workers to change dusty clothing after each shift , or if they have just finished a very dusty task to change at their next break , and
− providing workers with rubber boots and aprons .
When working outdoors , the ground can be covered with plastic sheeting and remaining dust can be removed using the above methods .
Management of wet slurry
Wet slurry is the resultant waste from water suppression . This slurry has the potential to build up from continuous processing using water suppression on equipment and machinery . The slurry is not hazardous while wet . However , if it dries , the dust can become airborne when disturbed and expose workers and others .
Wet slurry can be managed by :
− − − capturing or containing it through floor grading , grates , curbing and channelling keeping floors and surfaces wet , and regularly cleaning , including at the end of each day , to prevent wet slurry drying overnight .
Any wet slurry that is de-watered so that it is still wet , but of cake-like consistency , should be disposed of in a way that minimises the risk of dust being redistributed over the workplace . This may include covering the slurry , keeping it wet or bagging it before disposal .
Recycled water
Water that is recycled on-site for use in water suppression should be effectively filtered to remove silica dust and prevent contaminated water continually passing through the system . Without an appropriate filtration system there is a risk that continual recycling of water will increase the concentration of silica dust in the water over time and subsequently the level of silica dust in the mist arising from the water suppression activities .
Water recycling systems can filter slurry so that silica and other dust particles are removed from the water before it is re-used . These systems can include :
− a pit that collects slurry from drains − a slurry collection tank and filter press that compacts silica and other particles into a solid block for disposal − a slurry settlement tank and waste bag , where waste forms into a solid block , and − a filtered water tank that recirculates clean water back into the water supply .
Managing the risks of respirable crystalline silica from engineered stone in the workplace - Code of Practice 48 of 57