Comparative in-mine evaluation of carbon monoxide and smoke detectors.
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 9622, 1996 Jan; :1-7
To enhance the safety of mine workers through the use of improved atmospheric mine monitoring, a study comparing the responses of carbon-monoxide (630080) (CO) and smoke detectors to an in mine fire was conducted. Both diffusion and mechanical pump types of CO detectors were used. The smoke detectors used included two optical type detectors, one operating in diffusion mode and one in mechanical pump mode, and four ionization type detectors, three operating in diffusion mode and one in mechanical pump mode. Twelve experiments were conducted to study the effects of ventilation flow and entrainment at dead end crosscuts on the responses of CO and smoke detectors situated at nearly identical locations. The results showed that in most experiments, the smoke detectors alarmed before the CO detectors. Several conclusions were drawn from the study and the investigators make the following recommendations. They suggest that smoke detectors that have a continuous analog output signal be used whenever possible as part of a mine atmospheric monitoring system. These sensors give greater flexibility for setting alarm values for fire detection at low smoke levels. Smoke detectors that require relatively low maintenance, such as diffusion mode detectors, have reasonable expectations of being at least as effective as CO detectors. The results of airflow experiments showed that the effect of crosscuts on smoke travel time would be minimal for a particular smoke detector alarm level under normal airflow conditions. This finding should be incorporated in a mine fire location strategy. The authors conclude that smoke detectors, when incorporated into a mine atmospheric monitoring system, will complement CO detectors and thereby improve mine safety.
Underground-mining; Mining-industry; Coal-mining; Smoke-detection; Fire-prevention; Mine-fires; Safety-equipment; Warning-devices; Air-quality-monitoring; Combustion-products; Toxic-gases; Fire-protection-equipment
Pittsburgh Research Laboratory, P.O. Box 18070, Pittsburgh, PA 15236
Report of Investigations
NTIS Accession No.
Other Occupational Concerns
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 9622