Human body vibration effects

While discussing vibrations we may ask whether 60 cycle electromagnetic field fluctuations caused by electrical power transmission can affect the human body Considerable effort has been expended in addressing this question. The tentative conclusion is that such effects, if they exist, are extremely difficult to detect. However, the possibility has not been disproven.965... 

Vibrations of the human body or parts of the human body may cause annoyance, affect performance, or cause trauma. There are many conditions that produce local or general vibration of the body. Studies have identified some effects. Data in the literature are not complete, since experiments on vibration may cause injuries. Existing data provide a picture of vibration hazards and suggest controls to prevent vibration-induced health and safety problems. 

The effects of vibration on the human body will be dependent on the frequency, amplitude and exposure period and hence it is difficult to generalise on what they will be. However it is worthwhile remembering that in addition to the physiological effects vibration can also have psychological effects such as loss of concentration. 

Hearing in fish is processed in the inner ears, organs that receive input from vibrations created by sound. Fish do not have external ear canals like those in humans that connect the inner ear to the external environment. Sounds travel well in water and in fish s bodies, where they cause small bones in the inner ears to vibrate. The bones are denser than the rest of the animals tissues and therefore respond differently to sound waves. As the wavelengths of sounds vary, so do their effects on the small bones. These differences are registered by nerves and are interpreted as sound. 

Reducing the effects of vibration, shock, and impact on humans is effected in several ways (1) by isolation, to reduce the transmission of dynamic forces and accelerations to the body (2) by personal protective equipment, to distribute the dynamic forces over as large a surface area as possible and (3) by redesign, to reduce the source s vibration intensity. These subjects are considered after summarizing the occurrence of health effects from exposure to vibration, shock, and impact, which establishes the performance required of ameliorative measures. 

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