Which haul truck electrical cabinet cleaning method is most effective at reducing dust exposure of high voltage electricians
Journal of Health
School of Medical and Health Sciences
It is widely known that exposure to excessive inhalable dust particles increases the likelihood of developing a range of respiratory diseases, such as bronchitis and asthma. Dust particles also have additive and/or synergistic effects with other substances, increasing the risk of developing a number of other detrimental conditions. High voltage (HV) electricians performing maintenance on heavy mobile equipment (HME) are exposed to high levels of inhalable dust whilst they decontaminate haul truck electrical cabinets of dust prior to commencing any maintenance work. This project was completed at an iron ore mine site in the Pilbara of Western Australia. It aimed to assess the personal exposure to dust using a hand-held blower-only method for decontaminating compared with vacuuming the cabinet as much as possible preceding any blowing, and if a reliance on respiratory protective devices could be reduced. Six personal inhalable dust samples were collected for each method.
The results indicated that whilst there is a remarkable decrease in exposure levels when the vacuum method is used, statistical analysis determined that there was no difference between the two methods (p value = 0.061). Despite said reduction when vacuuming, the concentration of inhalable dust remained significantly greater than the adjusted occupational exposure level (OEL) of 8.7 mg/m3. Current use of loose-fitting powered air purifying respiratory (PAPR) must therefore remain mandatory as a minimum control. Recommendations to reduce the dust exposure of high voltage electricians include:
- Determine if the haul truck electrical cabinets can be modified to reduce the entry of dust into the cabinets
- Exploring mobile local exhaust ventilation (LEV) options that are designed to remove dust from haul truck electrical cabinet, and
- Respirator protection devices (RPDs) that provide a minimum of a P3 protection need to be used until exposures have been shown to have reduced to acceptable levels.