Mining Project: Analytical Enhancement of Rapid Quartz Analysis

Principal Investigator
Start Date 10/1/2022
Objective

Workers in mining and other occupational environments may be exposed to respirable crystalline silica (RCS) as part of a complex mixture of mineral airborne particles. Decreasing and preventing worker exposure to RCS is vital to preventing new incidence of silica-related diseases, such as silicosis. Mining environments are dynamic and in-field methods for monitoring RCS can allow for better control and mitigation of worker exposure. However, in-field methods, such as rapid quartz analysis (RQA) developed by NIOSH, must be accurate and also reasonably easy to use. This project aims to improve both the analytical accuracy and the usability of RQA to increase adoption and implementation in the mining industry.

Topic Areas

Research Summary

Approach

This project uses a two-pronged approach to improve the analytical capabilities of RQA and to improve the acceptance of RQA for new users at mine sites. In the first prong, samples of bulk mine dust will be obtained from mining operations, processed to isolate the respirable material, and analyzed by X-ray diffraction (XRD) to quantify the quartz (RCS) content and characterize the other minerals. Respirable samples on filter will  be analyzed by RQA; then data from RQA and XRD will be combined to construct predictive models that are better able to account for the presence of non-quartz minerals, with the ultimate goal of providing an accurate prediction of quartz.

In the second prong, current and prospective users of RQA at mines will be identified and interviewed to provide insight on how RQA is currently being used and to identify the barriers or challenges for implementation. Identifying common barriers will enable the design and creation of tools and resources, such as job aids and trainings, that can support and promote broader implementation of RQA in the mining industry.

Milestones and Accomplishments

The current project began October 1, 2022. The following milestones were accomplished in a related previous project, upon which the current project builds.

Description Audience Year
Interacted with 7 mining operations resulting in 2 mine visits and the collection of 21 new mine dust samples Health and safety professionals at mining operations; mine management 2022–2023
Analyzed preliminary data supporting efficacy of laboratory protocols for analysis of respirable mine dust via X-ray diffraction, including characterization of mineral content and quantification of quartz content (for ongoing development of predictive models for RCS) Academic researchers 2023
Tested and evaluated new quantification models with synthetic quartz samples Academic researchers 2022–2023

Planned Impacts and Outcomes

The planned outcome for this work is that mine operators adopt technologies that provide accurate and timely monitoring of worker exposures and incorporate these into their existing exposure assessment programs to mitigate exposure more effectively to respirable crystalline silica. This will be accomplished by improving the accuracy of the RQA measurement for more diverse mining environments and by creating tools and resources that support adoption of RQA. This will be measured by the number of new users of RQA and associated products such as the Field Analysis of Silica Tool (FAST).

Outputs

The current project began October 1, 2022, and has not yet produced any publications. Significant publications from the previous project, upon which this project builds, include the following:

Cauda E, Dolan E, Cecala A, Louk K, Yekich M, Chubb L, Lingenfelter A [2022]. Benefits and limitations of field-based monitoring approaches for respirable dust and crystalline silica applied in a sandstone quarry. J Occup Environ Hyg. Published online, 14 November, 2022.

Wolfe C, Chubb L, Walker R, Yekich M, Cauda E [2022]. Monitoring worker exposure to respirable crystalline silica: Application for data-driven predictive modeling for end-of-shift exposure assessment. Ann Work Expo Health 66(8):1010-1021.

NIOSH [2022]. Direct-on-filter analysis for respirable crystalline silica using a portable FTIR instrument. By Chubb LG, Cauda EG. Pittsburgh PA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2022–108, IC 9533.

Chubb LG, Cauda EG [2021]. A novel sampling cassette for field-based analysis of respirable crystalline silica. J Occup Environ Hyg 13(3):103-109.

Walker LT, Cauda E, Chubb L, Krebs P, Stach R, Mizaikoff B, Johnston C [2021]. Complexity of respirable dust found in mining operations as characterized by X-ray diffraction and FTIR analysis. Minerals 11(4):383-406


Page last reviewed: April 25, 2023
Page last updated: April 25, 2023