Mining Project: Development of an Aerosol Sampler for a Wearable Respirable Crystalline Silica Monitor

Research Summary

The monitoring capability of a near-real-time wearable respirable crystalline aerosol sampler device will alert miners/mining companies to hazardous RCS concentrations and the need for immediate respiratory protection. This will then be the impetus for the implementation of improved engineering controls and interventions before substantial exposures lead to irreversible lung fibrosis. RCS monitoring for exposure prevention can help stop a progressive massive fibrosis resurgence among miners across the United States and especially in central Appalachia and will ultimately save lives. This project goes hand in hand with the ongoing project, Advancing Exposure Monitoring for Airborne Particulates in Mining, which enabled RCS monitoring in the field.

While the pilot aimed to quantify RCS within minutes, the ongoing project made it possible to quantify RCS levels at the end of the work shift. The goal of both projects was to monitor workers in every mining environment in which the exposure to RCS is a concern. Workers in coal mines (underground and surface mines), in metal mines, and all types of metal/nonmetal operations including aggregates quarries and industrial mineral processing operations will benefit from this new technology. Professionals involved in health and safety and industrial hygiene activities can use the timely data on RCS concentrations to make informed decisions.

A compatible aerosol sampler for an infrared spectrometer was developed as a result of this project. The sampler rapidly amassed respirable dust over the infrared spectrometer detector for RCS quantification every 5 to 10 minutes. Due to the novel sampler design, the monitor can operate in near real time without the need for changing a filter or moving filter position. Another advantage is that diesel particulate matter will pass through the sampler without being collected and will not interfere with RCS detection. The laboratory work on the sampler development began in November 2021. The sampler was evaluated for its compatibility with a Fourier transform infrared spectrometer (FTIR), and the sampler and FTIR detected RCS in three minutes.