Experiments were conducted to evaluate the response characteristics of commercially available gas, smoke, and flame sensors to fires of common combustible mine materials. The experiments were conducted in the large-scale Fire gallery located at the National Institute for Occupational Safety and Health (NIOSH) Lake Lynn Laboratory (LLL) in Fairchance, PA, using Ponderosa Pine, Red Oak, Douglas-fir, high and low volatile coals, PVC and SBR conveyor belt, No. 2 diesel fuel, and diesel exhaust. All the experiments (except those using No. 2 diesel fuel and the diesel exhaust tests) were conducted in a similar manner, with combustible materials heated rapidly by electrical strip heaters producing smoldering fires that quickly transitioned into flaming fires. The sensors included a diffusion-type carbon monoxide (CO) sensor, photoelectric- and ionization-type smoke sensors, a video smoke/flame detector, and an optical flame detector. Simultaneous measurements were obtained for average gas concentrations, smoke mass concentrations, and smoke optical densities in order to quantify the levels of combustion products at the alert and alarm times of the sensors. Because the required sensor alarm levels are 10 ppm and 0.044 m−1 optical density for CO and smoke sensors, respectively, the different sensor alarms are compared to the time at which the CO and smoke reached these alarm levels (). In addition, the potential impact of using smoke sensors that have met the performance standards from accredited testing laboratories is also evaluated using the response of an Underwriters’ Laboratory (UL)-approved combination photoelectric/ionization smoke detector. The results are discussed relative to fire sensor needs that can have a positive impact on mine fire safety.
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机译:进行实验以评估市售的气体,烟雾和火焰传感器对常见可燃矿物质火灾的响应特性。实验是在宾夕法尼亚州费尔奇森的国家职业安全与健康研究所(NIOSH)湖林实验室(LLL)的大型火场中进行的,使用的是黄松,赤栎,花旗松,高挥发分和低挥发分煤,PVC和SBR输送带,2号柴油和柴油机废气。所有实验(使用2号柴油燃料和柴油机排气试验的实验除外)均以相似的方式进行,可燃材料被带状电加热器迅速加热,产生阴燃并迅速转变为明火。这些传感器包括扩散型一氧化碳(CO)传感器,光电型和电离型烟雾传感器,视频烟雾/火焰探测器和光学火焰探测器。同时获得平均气体浓度,烟气质量浓度和烟气光密度的测量值,以便在传感器的警报和警报时间量化燃烧产物的水平。因为对于CO和烟雾传感器,所需的传感器警报级别分别为10 ppm和0.044 m −1 sup>光密度,所以将不同的传感器警报与CO和烟雾达到这些警报级别的时间进行比较()。此外,还将使用经保险商实验室(UL)认可的光电/电离烟雾探测器组合的响应,评估使用符合认可测试实验室的性能标准的烟雾传感器的潜在影响。讨论了有关火灾传感器需求的结果,这些需求可能对矿山火灾安全产生积极影响。
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