NIOSHTIC-2 Publications Search

Multi-hazard sensor for minors.

Frish MB; Wainner RT; Rawlins T; Laderer M; Patel Ankit
Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R43-OH-008941, 2008 Sep; :1-17
NIOSH conducts activities to assure safe and healthful conditions for American workers. The mining industry presents particularly challenging safety and health needs. Miners are continuously exposed to methane, carbon monoxide, hydrogen sulfide, diesel fumes and particulate matter including coal dust. At low concentrations, chronic exposure to these airborne hazards can cause miner health problems, but at high concentrations the hazards are immediately life threatening due to their toxicity and potential for explosion. Thus, there is a need for technology able to measure the exposure of miners to these hazards as well as to warn miners of immediately dangerous conditions within or prior to entering potentially hazardous areas. This Research and Development project will lead to the development of a novel technology platform enabling laser-based sensor products to detect and measure these hazards from a distance. The sensors will warn miners prior to entry into a potentially explosive or toxic atmosphere, as well as monitor for hazards in physically inaccessible areas, simplifying mining operations and enhancing productivity. Currently, miners use cumbersome techniques that require sampling and analyzing mine air to sense these hazards. New laser-based techniques, developed by Physical Sciences Inc. (PSI) and now being adopted by the natural gas and other industries, enable sensing explosive or toxic environments from afar by illuminating the region of interest with a laser beam. To bring this technology to the mining industry, this project is intended to result, after Phases 1-3, in a novel suite of products that provide quantitative standoff sensing of the airborne mining hazards. Two technologies that PSI has previously developed into robust compact industrial sensor products form the foundation for the proposed miner safety sensor suite. These underlying technologies are standoff Tunable Diode Laser Absorption Spectroscopy (TDLAS) and laser Mie scattering. Using a transceiver similar in form to a handheld or helmet-mounted headlamp, the sensors illuminate an area with near-infrared light, projecting an eye-safe laser beam through airborne particles and onto mine walls and structures. Optical components within the transceiver or a companion receiver collect some of the laser light diffusely scattered from the walls and particles. Signal processors on battery-powered circuit boards analyze the collected laser light and determine the concentrations of each hazard along the path of the laser beam. Real-time audible alarms warn of immediate or imminent danger. Phase 1 demonstrated the feasibility of applying these technologies to measure hazardous concentrations of CO, CH4 , and dust with a sensor that is convenient for a miner to carry. That project, described in this report, provided a foundation for Phase 2. The Phase 2 Specific Aims are to: 1) design and engineer a novel multi-hazard sensor product platform architecture that simplifies configuring sensors to address a variety of mine safety needs; 2) demonstrate and evaluate the technology in test mines or operational mines; and 3) communicate results with the mining industry. Highlights/Significant Findings: The overall Phase I objective was to demonstrate the feasibility of developing the envisioned suite of miner safety sensor products. The Phase I specific aims were to: 1) Demonstrate the feasibility of adapting standoff TDLAS technology to sensing methane and carbon monoxide concurrently in a configuration suitable for helmet mounting and with the sensitivity and standoff distance appropriate for miner health and safety. 2) Evaluate the feasibility of adapting laser Mie scattering technology to helmet-mounted standoff sensing of explosible airborne particulate matter. The Phase I project was structured as a series of Tasks intended to achieve the following milestones: 1) Confirm with potential users the preliminary specifications of the sensor suite. 2) Build a prototype compact optical transceiver meeting the critical specifications for helmet mounting. 3) Demonstrate ability to measure both methane and carbon monoxide. 4) Define and model configurations of the explosible particle sensor. 5) Build and evaluate a breadboard particle sensor.
Workers; Mining-industry; Safety-measures; Health-care; Exposure-levels; Methanes; Diesel-exhausts; Particulates; Particulate-dust; Coal-dust; Inhalants; Air-contamination; Airborne-dusts; Airborne-particles; Hazards; Toxins; Explosive-dusts; Explosive-hazards; Analytical-processes; Monitors; Monitoring-systems; Samplers; Sampling-equipment
Michael B. Frish, Physical Sciences Inc., 20 New England Business Center, Andover, MA 01810-1077
74-82-8; 630-08-0; 7783-06-4
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Final Grant Report
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National Institute for Occupational Safety and Health
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Physical Sciences Inc., Andover, Massachusetts
Page last reviewed: March 25, 2022
Content source: National Institute for Occupational Safety and Health Education and Information Division