Vibrations of the human body . One of the most controversial issues in occupational hygiene is that of vibrations transmitted to the human body, because there are no conclusive studies that relate cause and effect between exposure to vibrations and the symptoms presented. And it is that vibrations act together with other factors such as high mental tension , noise and toxic substances present in a work environment.
Sometimes there is little depth in the handling of the subject due to the lack of professionalism and interest, and also a low demand for technical studies that enrich the knowledge of this phenomenon.
Summary
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- 1Origen
- 2 Features
- 3 Effects on the human organism
- 4 Control measures
- 1 Among the necessary control measures, the following are recommended:
- 5 Sources
Origen
Vibrations are defined as oscillatory movements of a body around a reference point and can occur as an effect of the operation of a machine or equipment. Its intensity is measured by a vibrometer , an instrument that determines the acceleration, speed and displacement in meters per second (m/sec).
High frequency (from 20 to 1000 Hz) can be produced by rotary or reciprocating, electric, pneumatic or percussive hand tools such as grinders , polishers , sanders , chainsaws , chipping hammers , concrete breakers , pneumatic hammers , drills , jigsaws , saws , riveters . If it is low (from 1 to 20 Hz), it is caused by passenger or freight transport vehicles, industrial equipment such as forklifts , forklifts , etc., bridges ,cranes , tractors and agricultural machinery , and public works vehicles. When it is very low (less than 1 Hz) it can be caused by airplanes , trains , ships , cars .
Features
The human body is often subjected to the effects of vibrations, that is, to oscillatory movements that can shake the entire body or be focused on a part of it, for example, on a specific muscle by vibratory massage to the skull when we wash our hair. hair .
Local vibration is widely used in sports, hairdressers, barbershops and in rehabilitation therapy for some diseases , its benefit lies in the fact that the frequency is low, below 20 hertz .
The alternating current that reaches our homes is 60 hertz or cycles and when by mistake we get in contact with it, it produces a vibration or shock that is assimilated according to the greater or lesser individual tolerance of the affected person. Therapeutic massage applied by ourselves or by qualified health personnel causes oscillatory movements that bring benefits, such as increased blood circulation , muscular relationship and anti- stress . Electrical stimuli and magnetotherapy for physiotherapy treatments also cause this effect.
Effects on the human organism
According to the frequency of vibration, there are various effects on the body .
When it is high, it can cause injuries to the joints such as the bones of the wrists, causing pain and limitations in movement, being able to observe these degenerative affections in the X- rays , it can cause vascular disorders in the hands, mainly with a sensation of lack of sensitivity in the hands. fingers , and digestive disorders .
As an effect of the low frequency, there is pain in the lower back, known as lumbago , herniated discs and other discomforts in the sciatic nerve , which can be increased by postural alterations or bad habits in the handling of any instrument, balance alterations and disorders of resonance vision . _ _
If the frequency is very low, it causes dizziness, affects the middle ear , so hearing decreases and in some cases even deafness due to intense noise, vomiting and other alterations of the Central Nervous System .
Control measures
Among the necessary control measures, the following are recommended:
- Mitigate the transmission of vibrations by placing handles or handles made of elastic or vibration-absorbing material.
- Reduce the exposure time, with pauses applied in the same way as those used for noise control.
- Use of gloves, belts, shoe inserts and anti-vibration wristbands.
- Establish procedures to keep the worker’s hands warm.
- Teach how to grasp the handle of the tools, which must be with the least force that allows the work to be carried out.
- Indicate ordering signs of the personal protection equipment that must be used.
- Establish epidemiological surveillance systems by the different competent agencies.
