Do You Understand What Is Electric Shock? EEP – First aid electric shock pdf Engineering Portal » Do You Understand What Is Electric Shock?
Share with your Facebook friends! What psychological effect does an electric shock? The most common reaction is to be thrown off the conductor as a result of the muscular contraction. The following text concentrates on the most common situation of a shock from a continuous power frequency ac waveform.
The magnitude of the current is the applied voltage divided by the impedance of the body. The overall circuit impedance will comprise the body of the casualty and the other components in the shock circuit, including that of the power source and the interconnecting cables. For this reason, the voltage applied to the body, which is commonly known as the touch voltage, will often be lower than the source voltage. 1000 Ω to 2500 Ω for most of the population, falling to around 750 Ω at voltages in excess of about 1000 V. For example, the impedance for a hand-to-chest path is in the order of 50 per cent of the impedance for a hand-to-foot path. Moreover, the current’s path through the body is a significant determinant of the effect on the heart. 1 summarizes the physiological effects of current passing through the body.
The effects relate to a hand-to-hand shock exceeding 1 s for a person in good health. A direct contact shock occurs when conductors that are meant to be live, such as bare wires or terminals, are touched. An indirect contact shock occurs when an exposed conductive part that has become live under fault conditions is touched, as depicted in Fig. Examples of an exposed conductive part are the metal casing of a washing machine and the metal casing of switchgear.
Painful sensation, increasing with current. Severe muscular contraction, sometimes severe enough to cause bone dislocation and fracture. Increased likelihood of respiratory failure. Burns at point of contact and in internal tissues. Cardiopulmonary resuscitation may be required. If the casualty is suffering from ventricular fibrillation, the only effective way to restore normal heart rhythm is by the use of a defibrillator. Where a defibrillator is not immediately available, the first aider should carry out cardiopulmonary resuscitation until either the casualty recovers or professional assistance arrives.
Pls kindly share for IEC standards related to controls voltages which are daily touch and control with our hands. To Know electricity you have to know safety first. That’s why we all should take care of Electricity :p since sometimes Electrical shock may kill us if we didn’t pay attention for the safety guidelines ! Hi, I have a question on table 16. Because I think if 80mA in Dc isn’t that much, or it will be totally different case in AC? Click here to cancel reply. Tell us what you’re thinking we care about your opinion!
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This article is about the ant Myrmecia pilosula. Shattuck C25795-1, ANIC32-023626, Myrmecia, near Bungendore, NSW. This species is known for the ability to jump long distances. Other ants and predatory invertebrates prey on the jack jumper.
Between 1980 and 2000, there were four deaths due to anaphylaxis from jack jumper stings, all of them in Tasmania. There, Smith described the specimens of a worker, queen and male. It is also named after the jumping-jack firecracker. Closeup view of a specimen. These ants attack with both its mandibles and sting.
Like its relatives, the ant possesses a powerful sting and large mandibles. These ants can be black or blackish-red in colour, and may have yellow or orange legs. The pubescence on the male is grey and long, and abundant throughout the ant’s body, but it shortens on the legs. The queen has a similar appearance to the workers, but its middle body is more irregular and coarser. Males also have much smaller triangular mandibles than workers and queens. The pubescence on the male’s gaster is white and yellowish. Jack jumper ants are abundant in most of Australia, being among the most common bull ant to be encountered.
The ant is rarely sighted in the northern regions of Western Australia. Two types of nests for this species have been described: one being a simple nest with a noticeable shaft inside, the other being a complex structure surrounded by a mound. They also camouflage their nests by covering leaf litter, debris and long grass over the nest. Nests can be found hidden under rocks, where queens will most likely form their colony, or around small piles of gravel instead.