The impact of laser radiation on the human
Occupational Diseases / / May 12, 2016
Optical quantum generators (lasers, lasers) - devices, which are the source of the light emission of an entirely new type.Unlike ray any known light source that carries the electromagnetic waves of different lengths, the laser beam is monochromatic (electromagnetic wave is strictly of the same length), has high spatial and temporal coherence (all waves are generated simultaneously in a single phase), a narrow directivity, hence the accuratethe focus in a small volume.Therefore, the laser power density per pulse can be enormous.
There are various types of lasers: solid-state, where the emitter is a solid - ruby, neodymium, etc., gas lasers (helium, neon, argon, etc.), Liquid and solid..The lasers can be operated in continuous or pulsed mode.
laser emission was characterized by the following basic parameters: wavelength (m) Power (W), power density (W / cm2), the radiation energy (J) and the angular divergence of the beam (arc min.).
Laser Scope is very broad: in various fields of national economy, in
uniqueness of the laser beam - to provide high-power radiation to a very small area, complete sterility - allows its use in surgery for tissue coagulation during operations on the retina, as a new research tool in experimental biology, cytology (the beam can reach the individual organelles, not. damaging the entire cell), etc.
growing number of individuals involved in the field of lasers;Thus, this type of radiation becomes important very serious professional and hygienic factors.
In a production environment the greatest danger is not to direct the light beam, the effect of which is possible only in case of gross violation of safety rules, and diffuse reflection and scattering of the beam (by visual inspection of the exposure to the beam on the target, under the supervision of the devices near the beam path, in reflectionfrom the walls and other surfaces).Particularly dangerous mirror reflective surfaces.Although the intensity of the reflected beam is small, but may exceed energy eye-safe levels.In laboratories where work with pulsed lasers, there are additional adverse factors: constant (80-00 dB) and pulse (up to 120 dB or more) noise, blinding light of the pump light, fatigue of the visual analyzer, neuro-emotional stress, gaseous impurities in the airmedium - ozone, nitrogen oxides;.. Ultraviolet radiation, etc.
Biological effects of laser
Biological effects of lasers is due to two main criteria: 1) the physical characteristics of the laser (laser wavelength, continuous or pulsed irradiation mode, pulse width, repetition speed, power density)2) characteristic absorption tissues.Properties most biological structure (absorbing, reflecting ability) influence the biological effect of laser effects.
laser action is multifaceted - electrical, photochemical;the main action - the heat.The most dangerous lasers with high pulse energy.
direct monochromatic light pulse causes in healthy tissue a local burn - coagulation proteins, local necrosis, sharply delimited from the adjacent area, aseptic inflammation with subsequent development of connective tissue scar.With intensive irradiation - vascularization disorders, bleeding in parenchymal organs.Repeated exposures pathological effect increases.The most sensitive eyes (cornea and lens focus light on the retina), and skin, especially pigmented.
In direct contact with the laser beam into the eye - the retina burn, it breaks.Can be hit the cornea, iris, lens, skin age.The defeat is usually irreversible.
Eyes dangerous not only direct, but also scattered radiation reflected from any surface.Prolonged exposure to the latter most often found needle, arrow-shaped, at least - point lens opacity.On the retina - bright, yellowish-white, depigmented lesions.In the study of the functional state of the visual analyzer are determined by reduction of light and contrast sensitivity, increasing the recovery time to adapt, change light sensitivity.Characteristic complaints of pain and pressure in the eyeballs, pain in the eyes, eye fatigue by the end of the day, headaches.
addition to the defeat of the body when working with lasers is developing a set of non-specific reactions from the various organs and systems.
common disorders clinic consists of autonomic dysfunction with the addition of neurotic reactions asthenic background.As the professional experience increases the frequency of neuro dystonia of hypotonic or hypertonic options, depending on the nature of the laser light (continuous, pulsed), as well as the degree of neuroticism.
also observed dysfunction of the vestibular apparatus in the direction of increasing and decreasing its excitability.The frequency of these disorders also increases with professional experience.
From biochemical parameters characterized by: increasing the level of ammonia in the blood, increasing the activity of alkaline phosphatase and transferases, changes in catecholamine excretion.
In experiments on animals with low energy intensity of the action marked changes in cerebral blood flow, coupled with changes in systemic hemodynamics.Laser energy is established effects on the hypothalamic-pituitary system.
disability With the development of functional disorders of the central nervous system, cardiovascular apparatus recommended treatment and a temporary transfer to another job;return to work at improving the condition (under medical supervision) and provided better working conditions.Eye involvement is a contraindication to further work with the laser.
rational organization of laboratories working conditions.laser placement in an isolated room.Alarm System, which provides safety during laser operation.Avoid the use of reflective surfaces.the laser beam should be directed to non-reflective and non-flammable background.Matte Painting walls - in bright colors.Ray screening (especially powerful JAG) on the way from the source to the lens.It is strictly forbidden the presence of people in the danger zone of the laser radiation in the laser.It is forbidden to stay in the lab who are not engaged in the laser service.Effective ventilation.General and local lighting.Strict compliance with electrical safety requirements, personal protective measures.The use of specially designed goggles (for each wavelength filter your paternal).Work under the overall bright light for the purpose of narrowing the pupil.When dealing with high energy to avoid contact with any part of the body by direct beam, it is recommended wearing a black felt or leather gloves.Strict ophthalmologic control.Preliminary and periodic medical examinations.