Respirable dust concentration at workstations in a gold mine processing plant

Author

Muchuweni, Ephraim

Title

Respirable dust concentration at workstations in a gold mine processing plant

Abstract

Background: Mining is one of the cornerstones of national economies, but is associated with serious environmental health risks, particularly from airborne dust in processing plants. Objectives: Respirable dust concentrations were measured at selected dusty workstations within a gold mine processing plant to assess legislative compliance with the WHO 24-hour guideline of 0.015 mg/m³. Methods: Area-based sampling was conducted using a Split II Haz-Dust Monitor over 8-hour shifts on 22 April 2025. Measured values were converted to 24-hour time-weighted averages using a standard extrapolation formula. Descriptive and inferential analyses were conducted using SPSS v27. Kruskal-Wallis test, post hoc pairwise comparisons using Dunn’s test with Bonferroni correction, was used for data analysis in SPSS. Statistical significance was considered at p  0.05.
Results: The 24-hour respirable dust concentrations ranged from 0.073 mg/m³ to 10.5 mg/m³ with a mean of 3.05±0.88SE mg/m³. The Shapiro-Wilk test indicated a non-normal distribution of the data (p = 0.228). A Kruskal-Wallis test revealed significant differences in respirable dust concentration across 13 workstations (H = 37.687, p = 0.002). Post-hoc Dunn’s tests with Bonferroni correction grouped the workstations into six distinct groups. All converted measured concentration exceeded the WHO 24-hour guideline of 0.015 mg/m³, with the lowest value approximately 15 times higher than the recommended limit.
Conclusion: Findings highlight significantly high ambient dust levels in gold processing areas, reinforcing the urgent need for improved air quality control.

Date

May 2025

Publisher

BUSE

Keywords

PM₂.₅

Respirable dust

Gold processing

WHO limit

Dust control

Supervisor

N/A