Comparison of real-time and traditional monitoring methods for diesel particulate matter in underground metal mines: A meta-analysis

ObjectiveTo conduct a meta-analysis of published studies to determine if a real-time instrument can be used as a screening tool to estimate the concentrations of diesel particulate matter (DPM) in air within an underground mine workplace. The instrument chosen for review is the TSI DustTrak. The DustTrak was chosen because of the growing popularity, ease of use, and relative low cost as compared to other real-time instruments used in the underground mining industry. Determination of acceptability for DustTrak use would be based on comparison of instrument results to monitoring results from the currently accepted pump-filter air sampling methods for DPM.MethodsAfter a comprehensive literature search, a total of two studies meeting requirements for a meta-analysis on performance of the DustTrak were identified and used for this analysis.ResultsMeta-analysis of the available DPM exposure monitoring data resulted in a Combined Pearson's Correlation Coefficient (CPCC) of 0.893 (p < 0.0001) weighted by the number of samples, the non-weighted CPCC of 0.874 (p < 0.0001), and a calculated R2 value for the linear regression of the combined studies of 0.797 (p < 0.0001).ConclusionsThe results from this meta-analysis are supportive of the DustTrak as an acceptable supplementary sampler (e.g., used to verify the adequacies of exposure controls) for providing acceptably accurate real-time concentration levels of DPM in air in an underground mining operation. Although the DustTrak correlates well with the NIOSH method, its monitoring results do consistently read higher than the NIOSH method.