4 February 2016
With wide spread acceptance that water storage tanks can’t simply be ‘fitted and forgotten’, the Health and Safety Executive regularly warn Engineers that suitable measures are required to ensure tanks are correctly specified, examined and maintained throughout their service life.
Corrosion of steel fasteners, black mould growth, osmotic blistering and leaking between panels are all common reasons why tanks fail and reasons called upon for tanks to be repaired and relined. There are now a range of advanced coatings to specify from, but does the removal of the failed lining need to be a costly disruption to service?
CSC Services are now able to offer a one-stop solution to this problem. The latest dustless blasting technology can be used to remove failed coatings and prepare surfaces to be relined. It can be used on a range of structures in addition to tanks including external pipework. It eliminates many of the problems typically associated with traditional stripping methods.
Vacuum blasting is a dust free process. All materials and old coatings when blasted from a surface are vacuumed back into the machine via a hose attached to the inside of the blast nozzle. This is of paramount importance given that dangerous levels of Silica (DUST) can be created when blasting materials such as concrete and masonry. Crystalline silica particles can cause lung disease and lung cancer. It only takes a very small amount of airborne silica dust to create a health hazard. The National Institute for Occupational Safety and Health (NIOSH) has a recommended exposure level (REL) of 0.05 mg/m3 to Silica.
As the blasted material is immediately contained the process causes less mess. This means there is less need for areas to be screened off for work to commence which will usually reduce the length of time that the service is disrupted. Workers using dustless blasting equipment do not need to be segregated from other workers. Precision dustless blasting is widely used by the NHS and in the food manufacturing industry where cleanliness is paramount.
The process is environmentally friendly and efficient. Precision dustless blasting can be used in confined spaces and will provide a suitable mechanical key to which a new coating system can bond to.
The latest WRAS approved Polyurea coating that CSC Services has added to its portfolio can also significantly reduce disruption to service. This has a very fast cure and set time (5-20 seconds), and can be applied in sub-zero temperatures. This enables repair and relining work to take place all year round. Polyurea is also abrasion resistant and highly chemical resistant meaning the coating can be guaranteed for longer than traditional coatings of this nature. Polyurea is currently pending DWI approval.