Response to Electrical Stimuli

GE Energy Services, Schenectady, NY
IEEE Industry Applications Magazine (Impact Factor: 0.35). 07/2009; 15(3):22 - 30. DOI: 10.1109/MIAS.2009.932362
Source: IEEE Xplore


Electrical safety is important in industrial work. This article provides considerable detail on how current can pass through different parts of the body and each parameter that can impede or limit the flow of current. Electric currents flowing through a human body can have varying effects, ranging from little or no perceptible effect, to shocking sensation, to possibility of electrocution, depending primarily on the magnitude and the duration of the current flow. The effect of current flow is a function of the applied voltage level, the duration of the exposure, and the resistances or impedances of the body and the other available current paths. A key consideration with energized objects is that, in order for the electric current to flow through the body, one body part must make contact with an energized object or conductor and another body part must make contact with the earth or an object or conductor that provides a path for the current to return to its source. This article supplies considerable detail on how currents can pass though different parts of the body and each parameter that can impede or limit that flow of current. The information presented indicates that the most likely scenarios for a dangerous condition would be that when a person comes in contact with an energized metallic object energized at 120 V and the person is barefoot and the ground is moist or wet as are the persons' hands or feet. Nearly, any other condition such as dry ground, rubber, or leather soled shoes; dry hands and so on have a lower probability of creating current flows that would be considered damaging or disruptive.

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    • "Experiments proved a relationship between the tolerable body current I and the current duration t expressed by a constant value I 2 t; this relationship is based on the body mass of the injured. In [11] the response to electrical stimuli are analyzed in strict reference to existing literature and in light of the data presented in [5] by the International Electrotechnical Commission. A preliminary consideration is about the obvious difficulty at carrying out experiments with volunteers when the most dangerous effects of currents need to be studied; difficulties also arise when electrical accidents must be investigated. "
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