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Electrical Safety Code Manual
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We have been manipulating power since the time of the caveman. About half a million years ago, mankind mastered fire. The energy source was easy, even for them, to understand; if you touched it, you would get burned. A 1000 years later, the ancient Greeks discovered that rubbing fur on amber caused a spark of energy, and by the seventeenth century, the differentiation between positive and negative currents was discovered. | electrical SAFETYCODE Manual A Plan Language Guide to National Electric Code OSHAand NPFA70E KIMBERLY KELLER Electrical Safety Code Manual This page intentionally left .