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Carbon Monoxide Analysis
Published in David G. Penney, Carbon Monoxide, 2019
This device was calibrated in outside air with the tip of the flame at the center etching. If the flame tip dropped below the lower etching while in the mine, this was an indication that there was insufficient oxygen to support life for much longer — that is, it was time to evacuate the mine. If the flame tip reached the upper etching on the glass chimney, combustible gases were accumulating and, sooner or later, with a source of ignition there will be an explosion — time to seek sunlight. As primitive as the device was, it undoubtedly saved many lives in poorly ventilated mines and shafts where there were gas accumulations of methane, CO, carbon dioxide, hydrogen sulfide, nitrogen (i.e., decreased oxygen concentrations), and other noxious and flammable gases. However, because the lower limit of explosibility of CO gas is 12.5% (125,000 ppm, or parts of gas per million parts of air), flame safety lamps arguably did little to protect miners from this gas alone (NIOSH, 1990). Significantly, this little lamp, as used in European and American mines, was the first semiquantitative device used to regularly monitor toxic, explosive gases with industrial hygiene significance in workplace atmospheres.
Flames
Published in J. F. Griffiths, J. A. Barnard, Flame and Combustion, 2019
J. F. Griffiths, J. A. Barnard
Quenching of flames is important in flame traps. Such devices are used to prevent flame propagation through flammable gases, as in the miner’s safety lamp, designed by Sir Humphry Davy, in which the lamp flame was surrounded by a fine copper gauze. The mesh size is crucial in determining whether or not the passage of a particular flame would be stopped. In industrial applications, flame traps frequently comprise an assembly of narrow bore, thin-walled tubes which have a minimal resistance to gas flow while preventing flame propagation.
Atmospheric Testing
Published in John F. Rekus, Complete Confined Spaces Handbook, 2018
Perhaps the first significant advance in gas detection instrumentation came in 1855 with the invention of the miner’s safety lamp by Sir Humphry Davy. The Davy lamp not only provided miners with illumination, but it also served as a combination oxygen and explosive gas detector.
Dimensional scaling of flame propagation in discrete particulate clouds
Published in Combustion Theory and Modelling, 2020
Fredric Y.K. Lam, XiaoCheng Mi, Andrew J. Higgins
The examination of how flames respond to heat losses reveals considerable insight into flame structure and dynamics. It could be argued that modern combustion science began in 1815 with Sir Humphry Davy's development of the safety lamp. In addition to its practical application in preventing mine explosions, the demonstration that a wire mesh can quench a flame made clear that it is the competition between heat generation and heat loss that determines criticality in flame propagation [1]. The seminal analytic treatment of this problem by Spalding showed that quenching corresponds to a criticality in the solution of the flame structure [2]. Modern asymptotic analysis revealed that the decrement in flame speed with increasing heat loss can be described mathematically by an eigenvalue solution for the flame speed, with the critical condition for flame quenching associated with a turning point in the solution [3,4].