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Vibration disease is a professional disease, the main etiological factor of which
is industrial vibration. There are the following concomitant occupational factors of
risk as the favourable background for the development of the disease: noise,
supercooling, significant muscle tension of shoulder, the forced position of the body.

It leads to the degeneration of biological tissues:
a) muscle atrophy;
b) loss of elasticity of blood vessels (become brittle, resulting in disturbed
blood supply);
c) loss of mobility of the tendons (spinal deformity);
d) loss of sensitivity of nerve endings, increased the fragility of hair and nails.
Local vibration acts somewhat differently in the human body:
a) vascular spasms, that start with the terminal phalanges, are extended to the
entire palm, forearm and cover the vessels of the heart;
b) there is deterioration in limb blood supply.
At the same time, there is an impact on the nerves, muscle and bone tissue.
This action is expressed in such forms:
c) in violation of the sensitivity of the skin;
d) in the ossification of the tendons and muscles;
e) pain and salt deposits in the joints of hands.
In the end, the deformation and decrease in joint mobility.
Especially harmful vibrations are with the frequency equal to the frequency of
the body and its organs (6–9 Hz); hands (30–80 Hz).

Methods of hygienical estimation of vibration:
 frequency (spectral) analysis of its parameters;
 integral estimation of the spectrum of the frequency parameters,
that are rationed;
 the dose of the vibration.
Under the permanent influence of the local and general vibration, the rationed
parameter is the mean-square value of vibration speed (v) and the vibration
acceleration (a) or their logarithmic levels Lv, La in dB in the range of octave bars
with the geometric center frequencies.
General vibration is rationed taking into account the sources of its origin and, as
mentioned earlier, is divided into transporting, transport-technological,
technological.

12.2 Protective Methods against the Harmful Effects of Vibration

The main directions for solving the problem of vibration protection are the
automation of production and the introduction of robotics.
Ways of protection against vibration:
1) reduction of vibration in the source of its origin;
2) vibration damper;

3) vibration extinction;
4) vibration isolation.

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