Hire and Rental News - February 2019

INDUSTRY IN FOCUS Silica exposure limits The workplace exposure standard mandatory limit for silica dust exposure in Australia is 0.1mg/m 3 averaged over an eight hour day, although the ACGIH have recommended this be limited to 0.025mg/m 3 . However, there is no evidence to support a safe level of silica dust exposure. Work Health and Safety (WHS) Regulation 50 states air monitoring by an occupational hygienist must be conducted every 12–18 months if there is health safety risk or if there is potential of exseeing the exposure limit. However, air sampling on its own is not enough. This exposure standard is being reviewed as a priority by Safe Work Australia. A draft report of the review was planned for release by the end of 2018. n Links: www.cancer.org.au/preventing- cancer/workplace-cancer/silica- dust.html www.safeworkaustralia.gov.au/ workplace-exposure-standards- review-methodology www.safeworkaustralia.gov. au/media-centre/collaborating- industry-tackle-silica-dust- exposure Cancer Council of Australia Table 1. Summary of control measures for silica dust ACTIVITY CONTROL Construction, planning and design For example, by: • using other materials (e.g. autoclaved aerated concrete) in place of concrete masonry • planning buildings with pre-built recesses for plumbing, gas and electric wiring • ordering the right size materials • getting materials cutw to size off-site Correct equipment • Use fibre cement sheet shears instead of circular saws. • Ensure the rock-drilling machines, have dust suppression features. • Vehicles (i.e. tractors, excavators and bulldozers) should have a dust collection system and an air conditioned cab with a filtered air supply. Filters should be cleaned and maintained regularly. Workshop ventilation Have enclosures or hoods and local exhaust ventilation (LEV) to remove the dust at the point it’s produced. Abrasive blasting WHS Regulations do not allow abrasives containing silica. Use metallic shot, slag products (ilmenite, garnet or staurolite) instead of sand. During blasting, containment methods such as blast-cleaning machines, cabinets and LEV should be used. On-tool extraction Use LEV that fits directly onto the hand-held machines. This is the most effective way of controlling dust. Water suppression To be used when LEV is not suitable. Water should be used through non-electric tools to wet dust down at the point of dust generation. For example, water should be provided to the blade when using saws; just wetting the material is not enough. Ensure equipment and work areas are cleaned regularly with water. Use water spray or rubber curtains around conveyor transfer points. Respiratory protective equipment (RPE) No RPE can prevent all silica dust from being breathed in and should be used in combination with other controls. RPE cannot protect you if it doesn’t fit properly. Employers should have workers fit tested and trained in their use and maintenance. This is even more important if you have facial hair. It is important to choose the right RPE for the job; use the AS/NZS 1715:2009 standards or watch this HSE video for guidance on the selection and use of RPE. Quit smoking Smoking reduces the lung’s ability to clear dust and increases the risk of lung cancer. PPE If possible wear disposable clothing at work. Before you leave work, shower and change into clean clothes. Do not take your dusty clothes home to wash. Administration Display warning signs if tasks create silica dust. Rotate staff to limit the time they are exposed. Locate silica dust work outdoors, away from other workers. If not possible, enclose the area with floor to ceiling plastic sheeting. Clean-up DO NOT ‘clean up’ with compressed air or by dry sweeping. Dust should be removed using an industrial HEPA (high-efficiency particulate air) filter vacuum, which should be cleaned and maintained regularly. Work examples of silica dust generation Examples of work activities that can generate respirable silica dust particles include: • during fabrication and installation of composite (engineered or manufactured) stone countertops; • excavation, earth moving and drilling plant operations; • clay and stone processing machine operations; • paving and surfacing; • mining, quarrying and mineral ore treating processes; • tunnelling; • construction labouring activities; • brick, concrete or stone cutting; especially using dry methods; • abrasive blasting (blasting agent must not contain greater than 1% of crystalline silica); • foundry casting; • angle grinding, jack hammering and chiselling of concrete or masonry; • hydraulic fracturing of gas and oil wells; and • pottery making. What diseases can silica dust cause? If a worker is exposed to and breathes in silica dust they could develop: • chronic bronchitis; • emphysema; • acute silicosis; -- can develop after a short exposure to very high levels of silica dust, within a few weeks or years, and causes severe inflammation and an outpouring of protein into the lung; • accelerated silicosis; -- can develop after exposures of 3 to 10 years to moderate to high levels of silica dust and causes inflammation, protein in the lung and scarring of the lung (fibrotic nodules); • chronic silicosis; -- can develop after long term exposure to lower levels of silica dust and causes fibrotic nodules and shortness of breath; -- can include progressive massive fibrosis where the fibrotic nodules in the lung aggregate; • lung cancer; • kidney damage; or • scleroderma; -- a disease of the connective tissue of the body resulting in the formation of scar tissue in the skin, joints and other organs of the body. P18 HIRE AND RENTAL NEWS FEBRUARY 2019