Quantitative Methane Plume Imager for Localization and Flow Rate Estimation in Mines

Project Summary Abstract NIOSH conducts activities to assure safe and healthful conditions for American workersThis proposed project addresses a NIOSH mission objective for innovative solutions that provide practical methods to identify and measure hazards at a reasonable cost in high risk occupationse gminingThe mining industry presents particularly challenging safety and health needsDespite well regulated safety proceduresaccidental explosions and toxic gas inhalation continue to cause coal miner deathsTo help prevent such tragediestechnologies are needed that sense and measurefrom a distanceconcentrations of explosive or other life threatening hazards including methaneCHcarbon monoxideCOhydrogen sulfideH Sand dustThese technologies can warn miners of immediately dangerous conditions within or prior to entering potentially hazardous areasLaser based technologiessuch as the widely deployed backscatter Tunable Diode Laser Absorption SpectroscopyTDLASdeveloped and commercialized by Physical Sciences IncPSIfor natural gas leak surveying using handheld laser toolsenable sensing explosive or toxic environments from afar by safely illuminating the region of interest with a laser beamIn previous NIOSH CDC OMHSR researchwe have demonstrated the use of this technology to detect areas of high methane concentrations along mine wall facesRecentlywe developed the ability to utilize this technology to create quantified images of small methane plumesand to utilize the quantitative information to deduce the plume fluxi eemission flow rateThis proposed project is intended to incorporate this novel capability into lightweight handheld tools that enable visualization and quantification of potentially hazardous methane emission sourcesas well as detection of stagnant methane pocketsin coal minesThese tools will enable warning of immediately dangerous conditions prior to miners entering a hazardous area as well as continuous inspection for explosive gas accumulations during cutting of mine face wallsThe Phase I objectives are todevelop an engineering prototypeandevaluate the prototype in laboratory and research mine environmentsThe Phase I specific aims are todevelop a prototype handheld imaging head with associated electronic components that can be used for field testingtest the prototypeanalyze data and report resultsTasks to achieve these aims includeintegrating laser beam launcher and steerer to the optical frameworkintegrating video cameraintegrating computer for instrument controldata acquisition and processingoverlaying concentration maps and video imagesimplementing flux computation routinescompleting tests in the laboratory and research mineandanalyzing test results Project Narrative The technology to be developed in this project protects the health and safety of miners by sensing from afarimagingquantifyingand providing early warning of dangerous conditions caused by emissions and accumulations of explosivetoxicor asphyxiating gases such as methane