Work in the copper mining industry is often associated with exposure to respirable dust and respirable crystalline silica. This exposure has the potential to cause silicosis, an incurable occupational respiratory lung disease. This study aimed at establishing the relationship between knowledge, attitudes, work behavioral practices and compliance with safety standards and workers’ exposure to respirable dust. A cross-sectional descriptive survey was conducted on 528 mine workers. The Statistical Package for Social Sciences (SPSS) was used for the descriptives. Structural equation modeling (SEM) with latent variables and partial least squares (LVPLS) analysis were employed to determine the relationship among these variables. The results indicated that of the four hypotheses, two were supported, and two were rejected, showing that there is a significant relationship between exposure to respirable dust and work behavioral practices, as well as compliance with safety standards. Knowledge and attitudes toward respirable dust exposure did not significantly influence exposure. According to the results from the survey, positive work behavioral practices as well as compliance with safety standards were significantly associated with exposure to respirable dust. It is recommended that mines should focus on the miners’ work behavioral practices and compliance with safety standards.

Since the 1920s, Zambia’s mining sector has experienced growth, which has increased the number of mine workers employed in the industry. Consequently, the potential for occupational exposure and prevalence of occupational diseases have also increased. Unfortunately, Zambia does not currently have legislative guidelines for workplace air monitoring and compliance. This study’s objectives were to evaluate copper miners’ personal exposure to respirable dust and respirable crystalline silica (RCS) and to assess workplace compliance using the European Standard for workplace air monitoring and measurement (EN689:2018). This cross-sectional study collected 100 personal respirable dust exposure samples at a Zambian copper mine in 2023. These samples were weighed using NIOSH method 0600 and analyzed for crystalline silica using Fourier transform infrared spectroscopy (KBr pellet) (NIOSH method 7602). Additionally, 253 respirable dust exposure measurements collected at the mine between 2017 and 2022 were included for comparison. The median respirable dust exposure for the 2023 exposure measurements was 0.200 mg/m³ (95th percentile 2.871 mg/m³) compared to 0.400 mg/m³ (95th percentile 3.050 mg/m³) for the historic data. The median RCS exposure was 0.012 mg/m³ (95th percentile 0.163 mg/m³). Using EN689:2018, it was found that from 15 work areas, only six work areas complied with the standard for respirable dust exposure and only seven work areas complied with the standard for RCS exposure. At the mining site, several work areas had substantial exposure to respirable dust and RCS. Therefore, management needs to prioritize these areas when implementing control measures to reduce dust exposure. For the Zambia mining industry to manage exposure to respirable dust and RCS, it is necessary to implement standardized monitoring strategies. This study has demonstrated that EN689:2018 can be used successfully to determine compliance among Zambian mining work areas.

Introduction: Overexposure to respirable crystalline silica (RCS) can lead to the development of silicosis and other respiratory diseases. The mine under study was reported to have the highest number of certified cases of pneumoconiosis in Zambia in 2015, and in 2008, a study revealed that 56% of the RCS samples exceeded 0.05 mg/m3. This study aims to assess occupational exposure to RCS at this underground copper mine. Method: In this cross-sectional study, personal exposure monitoring was conducted using National Institute for Occupational Safety and Health’s methods 0600 and 7602 (KBr pellet), and 114 samples were collected. Gravimetric analysis of respirable dust (RD) samples and quantification of RCS were performed at an ISO 17025:2005 accredited analytical laboratory. BOHS-NVvA 2022 standard was used for determining activity areas’ overexposure. Results: The median, 95th percentile (P95), and maximum (Max) RD concentrations were 0.279, 1.650, and 3.7 mg/m3, respectively. For the RCS exposure, the median, P95, and Max RCS exposure concentrations were 0.02, 0.179, and 0.548 mg/m3, respectively. Thirteen (11.7%) of the 111 samples had exposure exceeding the Republic of South Africa (RSA) TWA-OEL of 0.1 mg/m3, and 11 out of 18 activity areas were statistically overexposed to RCS when applying the BOHS-NVvA 2022 standard. Discussion: The number of RCS samples exceeding 0.05 mg/m3 reduced from the 67% recorded in 2008 to 32.4% in this study. One factor that could have led to this reduction is the mine not working at full capacity during the sampling period. However, the lack of adherence to the occupational health and safety (OHS) guidelines by the miners still leads to personal exposure above the limits set by various countries. Conclusion: Exposure to RCS in more than half of the activity areas was not under control. Routine RCS monitoring in Zambian mines should be mandatory, as this is not an isolated case, though it is more of a challenge at this mine because of the high percentage of RCS in RD samples (18.5%). Miners should be continuously trained on the importance of adhering to the OHS guidelines. Furthermore, Zambia should consider adopting the RSA occupational exposure limit for RCS and the BOHS-NVvA 2022 standard for exposure level compliance testing.

Work in the copper mining industry is often associated with exposure to respirable dust and respirable crystalline silica. This exposure has the potential to cause silicosis, a non-curable occupational respiratory lung disease. This study aimed at establishing the relationship between knowledge, attitudes, work behaviour and practice, compliance with safety standards and exposure to respirable dust. A cross-sectional descriptive survey was conducted on 528 mine workers. Statistical package for social sciences (SPSS) was used for descriptives. Structural Equation Modelling (SEM) with latent variables and partial least-squares (LVPLS) analysis was employed to determine the relationship among these variables. The results indicated that of the four (4) hypotheses, two (2) were supported and two (2) were rejected showing that there is a significant relationship between exposure to respirable dust and work behaviour and practice, as well as compliance with safety standards. Knowledge and attitudes towards respirable dust exposure did not significantly influence exposure. According to the results from the survey, positive work behaviour and practice as well as compliance with safety standards was significantly associated with exposure to respirable dust. It is recommended that the mine should focus on the miners’ work behaviour and practice and compliance with safety standards.

Mine workers are occupationally exposed to respirable dust, which can cause irreversible lung diseases and controlling exposure concentrations to as low as reasonably practicable is, therefore, essential. To implement exposure reduction strategies and adequately manage exposure to hazardous chemicals, exposure needs to be measured and recorded according to a standard exposure management plan. This study aimed to assess the available respirable dust exposure data measured between 2017 and 2022 in various work areas and job categories at two mining shafts and a concentrator plant of a Zambian copper mine. Additionally, the monitoring program implemented at the mine was assessed for appropriateness. Descriptive data analysis was used to create an exposure matrix comprising 253 exposure measurements. Approximately 5.6% of the measured concentrations exceeded the South African time-weighted average occupational exposure limit (TWA-OEL) of 3 mg/m³. The geometric means of respirable dust exposure for shaft A, shaft B and the concentrator plant were 0.44 mg/m³, 0.44 mg/m³, and 0.68 mg/m³, respectively. The work areas with the highest maximum exposure results were the tipping area (18.0 mg/m³) at shaft A, the sump and waste bin (8.05 mg/m³) at shaft B and the screening (10.8 mg/m³), secondary crusher (14.0 mg/m³), foreign ore bin (4.43 mg/m³), and tertiary crusher (5.07 mg/m³) areas at the concentrator plant. It was found that the monitoring strategy implemented at the mine was flawed and did not collect a sufficient number of samples in each area during each year to make rigorous statistical assessment possible. This study highlights the sampling strategy’s shortcomings and recommends adopting a standardized monitoring strategy, such as EN689, to improve the respirable dust monitoring program at the mine. Additionally, this strategy can be implemented across Zambia and, if implemented correctly, it has the potential to be improve exposure monitoring across the country as no standard sampling strategy is currently enforced by the Government.