Abstract:
The South African mining industry is one of the largest producers of platinum (Pt) in the
world. Workers in this industry are exposed to significant amounts of dust, and this dust consists
of particles sizes that can penetrate deep inside the respiratory region. A cross-sectional study was
conducted to evaluate dust exposure risk at two Pt mine waste rock crusher plants (Facility A and
B) in Limpopo, South Africa. Workers’ demographic and occupational information was collected
through a structured questionnaire, a walk-through observation on facilities’ processes, and static
dust sampling for the collection of inhalable and respirable dust particles using the National Institute
for Occupational Safety and Health (NIOH) 7602 and the Methods for Determination of Hazardous
Substance (MDHS) 14/4 as guidelines. Only 79% of Pt mine workers, used their respiratory protective
equipment (RPE), sixty-five percent were exposed to work shifts exceeding the recommended eight
hours and 8.8% had been employed for more than ten years. The mean time-weighted average (TWA)
dust concentrations between Facility A and B showed a significant di erence (p < 0.026). The Pt mine’s
inhalable concentrations (range 0.03–2.2 mg/m3) were higher than the respirable concentrations (range
0.02–0.7 mg/m3), however were all below the respective international and local occupational exposure
limits (OELs). The Pt mine’s respirable crystalline silica (SiO2) quartz levels were all found below the
detectable limit (<0.01 mg/m3). The Pt miners had increased health risks due to accumulated low
levels of dust exposure and lack of usage of RPE. It is recommended that an improved dust control
program be put in place which includes, but is not limited to, stockpile enclosures, tire stops with
water sprays, and education on the importance of RPE usage.
