Matthew E. Benfer, Daniel T. Gottuk
\nHughes Associates Inc., USA<\/p>\n
Presented at the International Symposium on Fire Investigation Science and Technology, 2012<\/p>\n
ABSTRACT<\/p>\n
Although significant casualties and damage are attributed to electrical fires, there is still much uncertainty\u00a0in clearly identifying forensic indicators of electrical components post-fire to be able to justify whether the\u00a0component damage was a result of the fire (i.e., a fire victim) or whether it signifies a cause. The objective of this\u00a0study was to assess the damage and potential forensic signatures of a range of electrical receptacle configurations\u00a0exposed to two types of fires in order to provide a technical basis for realistic electrical fire scenarios, improving fire\u00a0scene interpretation, and evaluating the utility of forensic analysis techniques. Specifically, the approach was to,\u00a0first, characterize the damage (e.g., location of damage, melt, arcing, etc.) to receptacle configurations that have\u00a0been the source of overheating and compare this to data for receptacles exposed to fire. A second objective was to\u00a0characterize the similarities and differences between arcing and melting in receptacle components and wiring.<\/p>\n
Laboratory testing evaluated the impact of a wide range of variables on the formation of overheating connections in\u00a0residential duplex receptacles. Two types of receptacle configurations have been evaluated: 1) those focused on\u00a0terminal connections and 2) those focused on plug connections. Testing included 528 receptacle trials, 408 trials\u00a0with various terminal connections and 120 trials with various plug connections. Thirteen pre-fabricated wall\u00a0assemblies of 36 receptacles were placed in 8 compartment fire tests and 5 furnace fire tests. The variables evaluated\u00a0in the fire exposure testing included: the receptacle material, materials of the receptacle faceplate and box, terminal\u00a0torque, and energized state of the receptacle. A portion of receptacles in the fire exposure testing had overheated\u00a0connections that were created in the laboratory testing. These receptacles were used to assess whether evidence of\u00a0overheating would persist after a fire exposure. All receptacles were documented for damage to the receptacle,\u00a0faceplate, and outlet box including any arcing, overheating, and\/or melting.<\/p>\n
The results of laboratory testing indicate that only the loosest connections tend to form significant overheated\u00a0connections irrespective of other variables such as receptacle materials and installation. Characteristics of damage\u00a0to receptacles as a result of overheating have been identified and have been found to persist even after fire exposure.\u00a0In addition, locations of arcing within receptacles as a result of fire exposures were identified and characterized. The\u00a0location of arcing is primarily dependent on the duration and intensity of the fire exposure, as well as the\u00a0construction and materials of the receptacle, outlet box, and faceplate.<\/p>\n
Download the complete paper<\/a> here<\/p>\n","protected":false},"excerpt":{"rendered":" Matthew E. Benfer, Daniel T. Gottuk Hughes Associates Inc., USA Presented at the International Symposium on Fire Investigation Science and Technology, 2012 ABSTRACT Although significant casualties and damage are attributed to electrical fires, there is still much uncertainty\u00a0in clearly identifying forensic indicators of electrical components post-fire to be able to justify whether the\u00a0component damage was … Continue reading Fire Effects on Receptacles<\/span>