Chapter - I
INTRODUCTION
India is the seventh largest country by area and the second most populated country in the world with a population of 1,210.6 million (623.1 million males and 587.5 million females). Seventy per cent of the country's population is reliant on agriculture and related activities. The agriculture sector offers a livelihood to about 64 per cent of the labor. This force contributes nearly 26 per cent of GDP and accounts for about 18 per cent share of the total value of the country’s exports. The net sown area is 141.5 million ha. The area and production of pulses, cereal and oilseeds crops in the year 2011 was 26.4, 100.27 and 272.24 million ha. and 17.09, 242.2 and 29.8 millions tons respectively…show more content… Many important mechanical vibrations in tractors lie in the very high frequency range corresponding to rotation speed of 60-6000 rpm. Vibration describes the physical energy from a vibrating object, and also what we feel when that energy is transmitted to us. The main terms used to define this movement are “amplitude” and “frequency”. There are two of vibration occurs on Tractors operators : “segmental vibration” exposure, and “whole body vibration” exposure. Segmental vibration exposure refers to exposure that is mainly transmitted to, and concentrated on, a specific part of the body – such as the hand, arm, or leg. Whole body vibration exposure is when vibration is transmitted throughout all or most of the body. The control of vibration has been limited to vertical vibration effects with respect to a seated operation. Horizontal (lateral and longitudinal) and angular (pitch, roll and yaw) accelerator inputs are also experienced by the seated operations. Design for vibration isolation and control requires detailed analysis or complex vibrations. The amplitude of average mechanical vibration measured at the tractor, which are functionally important with the engine running at its rated speed both on load and unload conditions. Exposure of the human body to vibration can result in biological, mechanical, physiological and psychological effects. The common severe health effects from temporary exposure to whole body vibration include headache, abdominal pain,fatigue, chest pain , nausea and dizziness (loss of balance). The long-term exposure include, lower back pain leads to cause damage to the spine, major curves in middle-lower portion of the spine (lumbar scoliosis) wear of the discs in between the vertebrae of the spine (disc disease) tears or damage to the discs in between the vertebrae of the spine (herniated discs) neck problems (Anon.