MDW Environmental Services was engaged to supervise and validate the decontamination of cores and core trays, when previous analysis indicated that contamination of lead dust found within the core stacks exceeded the NOHSC exposure standard.
Core stacks were transferred to a specialist facility where each core tray was individually cleaned, repacked with polyethylene wrapping and labelled. Each core was tested for surface contamination and potential airborne contamination in order to validate the cleaning process.
Airborne contaminants were sampled using principles outlined within AS3640-2009 Workplace Atmospheres (method for sampling and gravimetric determination of inhalable dust), to determine the concentrations of inhalable lead and zinc particulates that staff would potentially be exposed to through handling the cores and cores trays.
Surface sampling was conducted using moist swabs as per Method Number ID – 125G, which was adapted from the U.S. Environmental Protection Agency methodology by the Department of Environment and Conservation (DEC) in consultation with the Department of Health (DoH). This method was used to determine the background concentrations of lead and zinc remaining in the cores and established an understanding of potential concentrations staff would be exposed to through skin contact while handling the cores.
Results indicated the decontamination of the cores and core trays was successful and the concentrations of surface and airborne lead and zinc that remained, post cleaning, were below the required Occupational Health and Safety Regulations’ (Safe Work Australia) indicator values and NOSHC Exposure Standards.
MDW Environmental Services was pleased to assist the client in the successful decontamination of the cores and core trays to levels below workplace exposure levels, ensuring the health and safety of the employees.