laser safety radiation protection

The effect of lasers on the body depends on the radiation parameters (radiation power and energy per unit of irradiated surface, wavelength, pulse duration, pulse repetition rate, irradiation time, irradiated surface area), exposure localization and anatomical and physiological features of the irradiated objects.

Laser radiation is a kind electromagnetic radiation generated in the optical wavelength range of 0.1…1000 µm. Its difference from other types of radiation is monochrome, coherence and a high degree of directivity. Due to the small divergence of the laser beam, the power flux density can reach 10 16 ... 10 17 W/m 2 .

The effects of exposure (thermal, photochemical, shock-acoustic, etc.) are determined by the mechanism of interaction of laser radiation with tissues and depend on the energy and time parameters of the radiation, as well as on the biological and physics - chemical characteristics of the irradiated tissues and organs.

Laser radiation is especially dangerous for tissues that absorb radiation to the maximum. Relatively easy vulnerability of the cornea and lens of the eye, as well as the ability optical system eyes repeatedly increase the energy density (power) of radiation in the visible and near infrared range (780<л<1400 нм) на глазном дне по отношению к роговице делают глаз наиболее уязвимым органом.

When damaged, there is pain in the eyes, spasm of the eyelids, lacrimation, swelling of the eyelids and the eyeball, clouding of the retina, hemorrhage. Retinal cells do not regenerate after damage.

Ultraviolet radiation causes photokeratitis, mid-wave infrared radiation (1400<л<3000 нм) может вызвать отек, катаракту и ожог роговой оболочки глаза; дальнее ИК - излучение (3000<л<10 6 нм) - ожог роговицы.

Skin damage can be caused by laser radiation of any wavelength in the spectral range of 180…100,000 nm. The nature of skin lesions is similar to thermal burns. The severity of damage to the skin, and in some cases the whole body, depends on the energy of the radiation, the duration of exposure, the area of ​​the lesion, its localization, the addition of secondary sources of exposure (burning, smoldering). Minimal damage to the skin develops at an energy density of 1000…10000 J/m 2 .

Far infrared laser radiation (>1400 nm) is capable of penetrating through the tissues of the body to a considerable depth, affecting internal organs (direct laser radiation).

Long-term chronic action of diffusely reflected laser radiation of non-thermal intensity can cause non-specific, predominantly vegetative-vascular disorders; functional shifts can be observed from the side of the nervous, cardiovascular system, endocrine glands. Workers complain of headaches, fatigue, irritability, sweating.

The biological effects that occur when exposed to laser radiation on the human body are divided into two groups:

Primary effects - organic changes that occur directly in the irradiated tissues;

Secondary effects - non-specific changes that appear in the body in response to radiation.

The human eye is most susceptible to damage by laser radiation. A laser beam focused on the retina by the lens of the eye will look like a small spot with an even denser energy concentration than the radiation incident on the eye. Therefore, getting laser radiation into the eye is dangerous and can cause damage to the retina and choroid with impaired vision. At low energy densities, hemorrhage occurs, and at high energy densities, a burn, a rupture of the retina, and the appearance of eye bubbles in the vitreous body occur.

Laser radiation can also cause damage to the skin and internal organs of a person. Damage to the skin by laser radiation is similar to a thermal burn. The degree of damage is affected by both the input characteristics of lasers and the color and degree of skin pigmentation. The intensity of radiation that causes damage to the skin is much higher than the intensity that causes damage to the eye.

Lasers and radiation from them have been used by mankind for quite a long time. In addition to the medical environment, such devices are widely used in technical industries. They were adopted by specialists from the field of decorating and creating special effects. Now, not a single large-scale show is complete without a stage with laser beams.

A little later, such radiation ceased to take only industrial forms and began to occur in everyday life. But not everyone knows how the effect of laser radiation on the human body is reflected with regular and periodic exposure.

What is laser radiation?

Laser radiation is born according to the principle of creating light. In both cases, atoms are used. But in the situation with lasers, there are other physical processes, and the influence of an external electromagnetic field is traced. Because of this, scientists call the radiation from lasers forced or stimulated.

In the terminology of physics, laser radiation is called electromagnetic waves that propagate almost parallel to each other. Because of this, the laser beam has a sharp focus. In addition, such a beam has a small scattering angle, together with a huge intensity of influence on the surface that is irradiated.

The main difference between a laser and a standard incandescent lamp is the spectral range. The lamp is considered a man-made light source that emits electromagnetic waves. The lighting spectrum of a classic lamp is almost 360 degrees.

The impact of laser irradiation on all living things

Contrary to stereotypes, the effect of laser radiation on the human body does not always mean something negative. Due to the widespread use of quantum generators in various areas of life, scientists decided to use the capabilities of a narrow beam in medicine.

In the course of numerous studies, it became clear that laser irradiation has several characteristic properties:

• Damage from a laser can be produced not only in the process of direct exposure to the body from the device. Even scattered radiation or reflected rays can cause damage.
• There is a direct relationship between the degree of damage and the main parameters of the electromagnetic wave. The location of the irradiated tissue also affects the severity of the lesion.
• The negative effect of energy absorption by tissues can be expressed in thermal or light exposure.

But the sequence in case of laser damage always provides for an identical biological principle:

• an increase in temperature, which is accompanied by a burn;
• boiling of interstitial and cellular fluids;
• the formation of steam that creates significant pressure;
• explosion and shock wave destroying all tissues nearby.

Often, an incorrectly used laser emitter is, first of all, a threat to the skin. If the influence was especially strong, then the skin will look edematous, with traces of numerous hemorrhages. Also on the body there will be large areas of dead cells.

Such irradiation also affects internal tissues. But with large-scale internal lesions, the scattered effect of the rays is not as strong as the direct or reflected mirror effect. Such damage will guarantee pathological changes in the functioning of various body systems.

The skin that suffers the most is the protection of the internal organs of each person. Because of this, he takes most of the negative impact on himself. Depending on the different degrees of damage, redness or necrosis will appear on the skin.

The researchers concluded that dark-skinned people are less susceptible to deep-seated lesions due to laser irradiation.

Schematically, all burns can be divided into four degrees, regardless of pigmentation:

• I degree. It implies standard burns of the epidermis.
• II degree. Includes burns of the dermis, which is expressed in the formation of characteristic blisters of the surface layer of the skin.
• III degree. Based on deep burns of the dermis.
• IV degree. The most dangerous degree, which is characterized by the destruction of the entire thickness of the skin. The lesion covers the subcutaneous tissue, as well as the layers adjacent to it.

Laser eye lesions

In second place in the unspoken rating of the possible negative effects of the laser on the human body are lesions of the organs of vision. Short laser pulses can disable in a short period of time:

• retina,
• cornea
• iris,
• lens.

There are several reasons for such an impact. The main ones are:

• Inability to respond in time. Due to the fact that the pulse duration is no more than 0.1 seconds, a person does not have time to blink. Because of this, the eye remains unprotected.
• Slight vulnerability. According to their characteristics, the lens and cornea are considered vulnerable organs in themselves.
• Optical eye system. Due to the focusing of laser radiation on the fundus, the irradiation point, when it hits a retinal vessel, can clog it. Since there are no pain receptors there, damage cannot be detected instantly. Only after the scorched area becomes larger, the person notices the absence of part of the image.

To quickly navigate with a potential lesion, experts advise listening to the following symptoms:

• eyelid spasms,
• eyelid edema,
• pain sensations,
• retinal hemorrhage,
• turbidity.

The danger is added by the fact that laser-damaged retinal cells lose the ability to recover. Since the intensity of radiation affecting the organs of vision is lower than the identical threshold for the skin, doctors are calling for caution.

You should beware of infrared lasers of various types, as well as devices that generate radiation with a power of more than 5 mW. The rule applies to equipment that produces rays of the visible spectrum.

Relationship between laser wave and its scope

Each of the areas of application of laser radiation is guided by a strictly defined wavelength indicator.

This indicator directly depends on nature. Rather, from the electronic structure of the working fluid. This means that the medium where the generation of its radiation takes place is responsible for the wavelength.

There are different types of solid-state and gas lasers in the world. The beams involved must be one of the three most common types:

• visible,
• UV,
• infrared.

In this case, the operating range of irradiation can vary from 180 nm to 30 mnm.

Features of the effect of a laser on the human body are based on the wavelength. So, for example, a person responds faster to a green laser than to a red one. The latter is not safe for all living things. The reason lies in the fact that our vision perceives green almost 30 times more than red.

How to protect yourself from the laser?

In most cases, protection from laser radiation is needed by those people whose work is closely related to its constant use. If an enterprise has any type of quantum generator on its balance sheet, then its managers must instruct their employees.

Experts have developed a separate set of rules of conduct and safety that will protect the employee from the possible consequences of radiation. The main rule is the availability of personal protective equipment. Moreover, such funds can differ dramatically depending on the predicted degree of danger.

In total, the international classification provides for the division into four hazard classes. The appropriate marking must be provided by the manufacturer. Only the first class is considered relatively safe even for the organs of vision.

The second class includes direct-type radiation that affects the organs of the eyes. Mirror reflection is also included in the presented category.

Radiation of the third class is much more dangerous. Its direct effect threatens the eyes. Diffuse-type reflected radiation at a distance of 10 cm from the surface is no less dangerous. Skin lesions will occur not only with direct exposure, but also with mirror reflection.

In the fourth grade, both the skin and the eyes suffer from various exposure formats.

Collective protective measures at work include:

• special covers,
• protective screens,
• light guides,
• innovative tracking methods,
• alarm,
• blocking.

Of the relatively primitive, but effective methods, the fencing of the zone where irradiation is performed is distinguished. This will protect workers from accidental exposure through negligence.

Also, at especially dangerous enterprises, it is mandatory to use personal protective equipment for employees. They mean a special set of overalls. You can’t do without wearing goggles that provide a protective coating during work.

Laser gadgets and their radiation

Many are unaware of how serious the consequences of the uncontrolled operation of home-made devices with a laser principle can be. This applies to home-made structures like laser ones:

• lamps,
• pointer,
• flashlights.

This is especially true for high school students who seek to conduct a series of experiments without having an idea about the safety rules when designing them.

It is unacceptable to use home-made lasers in rooms where people are present. Also, do not direct the rays at glass, metal buckles and other objects that can give reflections.

Even if the beam is of low intensity, it can lead to tragedy. If you point the laser at the driver's eyes during active movement, he may go blind and lose control.

Under no circumstances should you look into the lens of the laser source. Separately, it should be taken into account that glasses for working with a laser must be designed for the wavelength that the selected devices will generate.

In order to prevent a serious tragedy, doctors are asked to listen to these recommendations and follow them at all times.

The influence of laser radiation on the human body has not been fully studied at the moment, but many are confident in its negative impact on all living things. Laser radiation originates according to the principle of creating light and involves the use of atoms, but with a different set of physical processes. It is for this reason that the effect of an external electromagnetic field can be traced with laser radiation.

Scope of application

Laser radiation is a narrowly directed forced energy flow of a continuous or pulsed type. In the first case, there is an energy flow of one power, and in the second, the power level periodically reaches certain peak values. The formation of such energy is assisted by a quantum generator, represented by a laser. The energy flows in this case are electromagnetic waves that propagate relative to each other only in parallel. Thanks to this feature, a minimum angle of light scattering and a certain precise directionality are created.

Sources of laser radiation based on its properties are widely used in various areas of human life, including:

• science - research and experiments, experiments and discoveries;
• military defense industry;
• space navigation;
• production area;
• technical area;
• local heat treatment - welding and soldering, cutting and engraving;
• domestic use in the form of laser barcode readers, CD readers, and pointers;
• laser deposition, which significantly increases the wear resistance of metals;
• creation of modern holograms;
• improvement of various optical devices;
• chemical industry - analysis and start of reactions.

Especially important is the use of devices of this type in the field of modern medical technology.

Laser in medicine

From the point of view of modern medicine, laser radiation is a unique and very timely breakthrough in the treatment of patients who need surgical intervention. The laser is actively used in the production of high-quality surgical instruments.

The indisputable advantages of surgical treatment include the use of a high-precision laser scalpel, which makes it possible to perform bloodless incisions in soft tissues. This result is ensured by almost instant adhesion of capillaries and small vessels. During the use of a laser instrument, the surgeon is able to fully see the surgical field. Tissues are dissected by laser energy flow at a certain distance, while there is no contact of the instrument with blood vessels and internal organs.

An important priority in the use of modern surgical instruments is represented by ensuring absolute maximum sterility. Due to the strict direction of the beams, all operations occur with minimal traumatization, while the standard rehabilitation period of the patients who underwent the operation becomes much shorter and full-fledged working capacity returns much faster.

A distinctive feature of the use of a laser scalpel during surgery today is painlessness in the postoperative period. The very rapid development of modern laser technology has contributed to a significant expansion of its application possibilities. Relatively recently, the properties of laser radiation were discovered and scientifically proven to have a positive effect on the condition of the skin, due to which devices of this type began to be actively used in dermatology and cosmetology.

Areas of medical application

Medicine is by far not the only, but very promising area of ​​application of modern laser equipment:

• the process of epilation with the destruction of hair follicles and effective hair removal;
• treatment of severe acne;
• effective removal of birthmarks and age spots;
• skin resurfacing;
• therapy of bacterial lesions of the epidermis with disinfection and destruction of pathogenic microflora;
• prevention of the spread of infection of various origins.

The very first industry in which laser equipment and its radiation began to be actively used is ophthalmology. The areas of eye microsurgery in which laser technology is widely used are:

• laser coagulation in the form of the use of thermal properties in the treatment of vascular eye diseases, accompanied by damage to the vessels of the retina and cornea;
• photodestruction in the form of tissue dissection at the peak power of laser equipment in the treatment and dissection of secondary cataracts;
• photoevaporation in the form of prolonged thermal exposure in the presence of inflammatory processes of the optic nerve, as well as in conjunctivitis;
• photoablation in the form of a gradual removal of tissues in the treatment of dystrophic changes in the eye cornea, the elimination of its opacity, in the surgical treatment of glaucoma;
• laser stimulation with anti-inflammatory and resolving effects, which significantly improves eye trophism, as well as in the treatment of scleritis, exudation inside the eye chamber and hemophthalmos.

Laser irradiation is widely used in the treatment of skin cancer. Modern laser equipment shows the greatest efficiency in the removal of melanoblastoma. This method can also be used in the treatment of cancer of the esophagus or tumors of the rectum in stages 1-2. It should be noted that in conditions of too deep location of the tumor and multiple metastases, the laser is practically not at all effective.

Danger of laser radiation

At the moment, the negative impact of laser radiation on living organisms is relatively well studied. Irradiation can be scattered, direct and reflected. Negative impact causes the ability of laser devices to emit light and heat fluxes. The degree of damage directly depends on several factors at once, including:

• electromagnetic wave length;
• site of localization of negative impact;
• tissue absorption capacity.

The eyes are most susceptible to the negative effects of laser energy. It is the retina of the eye that is extremely sensitive and can receive burns of varying severity.

The consequences of this influence are the partial loss of vision by the patient, as well as complete and irreversible blindness. Sources of negative radiation are most often represented by various infrared devices emitting visible light.

Symptoms of damage to the retina, iris, lens and cornea with a laser:

• soreness and spasms in the eyes;
• severe swelling of the eyelids;
• hemorrhages of varying degrees;
• clouding of the eye lens.

Irradiation of moderate intensity can cause thermal burns of the skin. At the point of contact between the laser equipment and the skin, in this case, a sharp increase in temperature is noticeable, accompanied by boiling and evaporation of the interstitial and intracellular fluid. In this case, the skin acquires a characteristic red coloration. Under the action of pressure, ruptures of tissue structures occur and edema appears, which can be supplemented by intradermal hemorrhages. Subsequently, necrotic areas are observed at the burn sites, and in the most severe cases, noticeable charring of the skin occurs.

Signs of negative impact

A hallmark of a laser burn are clear boundaries on the affected areas of the skin with bubbles that form directly in the layers of the epidermis, and not under it. Diffuse skin lesions are characterized by an almost instantaneous loss of sensation, and erythema appears several days after exposure to radiation.

The main features are presented:

• changes in blood pressure;
• slow heartbeat;
• increased sweating;
• unexplained general fatigue;
• excessive irritability.

A feature of the laser radiation of the infrared spectrum is the penetration deep inside, through tissues, with damage to internal organs. A characteristic difference of a deep burn is represented by the alternation of healthy and damaged tissues. Initially, when exposed to radiation, people do not experience tangible pain, and the liver is one of the most vulnerable organs. In general, the impact of laser radiation on the human body provokes functional disorders in the central nervous system and cardiovascular activity.

Protection against negative impact and precautions

The greatest risk of exposure occurs in people whose activities are directly related to the use of quantum generators. According to the basic sanitary standards adopted today, radiation classes 2, 3 and 4 are dangerous for humans.

Technical protective methods are presented:

• competent planning of industrial premises;
• correct interior decoration without mirror reflection;
• appropriate placement of laser systems;
• fencing zones of possible exposure;
• compliance with the requirements for the maintenance and operation of laser equipment.

Personal protection includes special goggles and overalls, safety screens and housings, as well as prisms and lenses to reflect rays. Employees of such enterprises should be regularly sent for preventive medical examinations.

At home, you must be careful and be sure to adhere to certain rules of operation:

• do not direct radiation sources at reflective surfaces;
• do not direct laser light into the eyes;
• Keep laser gadgets out of the reach of small children.

The most dangerous for the human body are lasers that have direct radiation, high intensity, narrow and limited beam directivity, as well as too high radiation density.

Human - this is industry, medicine, scientific research, environmental monitoring, etc. Laser radiation (LI), like other types of radiation, has an adverse effect on the human body. Continuously emitting lasers produce an intensity on the order of $10$ W/cm2, which is quite enough to melt and vaporize any material. The radiation intensity during the generation of short pulses sometimes reaches more than $10$ W/cm2. To imagine this value, it should be noted that near the Earth's surface, the intensity of sunlight is only $0.1$…$0.2$ W/cm2. LI is optical coherent radiation, which has a high directivity and high energy density.

The radiation is formed in the active medium, which is the main element of the laser, and in order for it to be formed, it is necessary:

1. Light from non-laser sources;
2. Discharge of electricity in gases;
3. Chemical reactions;
4. Electric beam bombardment and other methods.

The optical resonator is formed by mirrors, between which the active medium is located, it can be a solid material - glass, plastic, rubies - can be represented by semiconductors, liquid with organic dyes, gas, etc. Lasers can be pulsed and continuous.

According to their physical and technical parameters, lasers are classified:

1. Design version:

   • Stationary lasers;
   • Mobile lasers;
   • open lasers;
   • closed lasers.

2. Radiation power:

   • Heavy duty lasers;
   • Powerful lasers;
   • Medium power lasers;
   • low power lasers.

3. Working mode:

   • CW lasers;
   • Pulsed lasers;
   • Q-switched pulsed lasers.

4. Heat dissipation method:

   • Naturally cooled lasers;
   • Forced water-cooled lasers;
   • Forced air-cooled lasers;
   • Lasers with forced cooling by special liquids.

5. Purpose:

   • Technological lasers;
   • Lasers are special;
   • Research lasers;
   • Lasers are unique.

6. Pumping method:

   • Pumping by chemical excitation;
   • Pumping by passing high-frequency current;
   • Passing a pulsed current;
   • By passing direct current;
   • Pumping with pulsed light;
   • Pumping with constant light.

7. The length of the generated light wave:

   • infrared lasers;
   • Visible light lasers;
   • ultraviolet lasers;
   • X-ray lasers;
   • submillimeter lasers.

8. For the active element:

   • Gas dynamic lasers;
   • Solid state lasers;
   • Semiconductor lasers;
   • Liquid lasers;
   • Gas lasers.

Laser radiation and the human body

All lasers, based on the degree of their danger to workers, are divided into 4 classes:

1. Do not pose a radiation hazard to human skin and eyes;
2. Both direct and specularly reflected radiation present a great danger to the eyes;
3. All three radiations - direct, specularly reflected and diffusely reflected - at a distance of $0.1$ m from the reflecting surface are dangerous. There is also the danger of skin exposure;
4. Hazard from diffusely reflected radiation at a distance of $0.1$ m from a diffusely reflective surface.

In the human body, laser radiation can cause pathological changes, disorders of the organs of vision, the central nervous system and the autonomic system. Laser radiation has a negative effect on the internal organs of a person - the liver, kidneys, spinal cord, etc. The resulting superficial burns - main pathophysiological effect of irradiation.

Class $II$, $III$, $IV$ lasers are obligatorily marked with laser hazard signs and equipped with signaling devices for the entire period of operation. To prevent the radiation from spreading beyond the processed materials, $III$ and $IV$ class lasers are equipped with special screens. For their production, fire-resistant, non-melting, light-absorbing material is used. The control of such lasers is remote.

For laser radiation installed limit levels. These levels are determined taking into account the region of the spectrum separately for the eyes and skin. Laser workers should undergo both a preliminary and an annual medical examination. For $II$…$IV$ lasers, workers must use personal eye protection, and for $IV$ lasers, protective masks. Depending on the wavelength of the radiation, the lenses of goggles can be colorless or orange, blue-green.

All the dangers of laser radiation are divided into primary– laser machine and secondary– in the process of interaction between laser radiation and the target.

1. Primary hazards:

   • Direct laser radiation;
   • Electrical voltage;
   • Light emission;
   • acoustic noise;
   • Vibration accessories;
   • Gases polluting the air emitted from the unit of the installation;
   • X-ray radiation at voltages above $15$ kV.

2. Secondary hazards:

   • Reflected laser radiation;
   • Aerodisperse systems;
   • Acoustic noise;
   • Radiation of a plasma torch.

Rationing of laser radiation

There are two scientifically based approaches to the regulation of laser radiation:

1. The first concerns the damaging effects of tissues or organs directly at the site of irradiation;
2. Second the approach concerns detectable changes in systems and organs that have not been directly affected.

At the core hygienic regulation are the criteria for biological action.

Based on this, the range of laser radiation was divided into areas:

1. Ultraviolet region - from $0.18$ - $0.38$ microns;
2. Visible area - $0.38$ - $0.7$5 microns;
3. Infrared near region - $0.75$ - $1.4$ µm;
4. The infrared far region is over $1.4$ microns.

Remark 2

Justification of hygienic standards is difficult due to the fact that the wavelength range is wide, the parameters of laser radiation and biological effects are diverse. Experimental and clinical verification requires time and money, therefore, mathematical modeling is used to clarify and develop the maximum permissible levels of LI.

Mathematical models, of course, take into account the nature of the energy distribution and the absorption characteristics of the irradiated tissues. The method of mathematical modeling of the main physical processes was used in determining and refining the LI PD. It was included in the latest edition of sanitary norms and rules for the design and operation of lasers - SNiP No. 5804-91.

The developed norms took into account the results of scientific research and the main provisions of the documents:

1. SaNiP device and operation of lasers № 2392-8 1;
2. IEC Standard (first edition, $1984$);
3. Changes to the International Electrotechnical Commission Standard ($1987, publication $825).

These norms are subject to application and this is evidenced by the Letter of Rospotrebnadzor dated $16$.$05$.$2007$ № 0100/4961-07-32 . Maximum allowable levels of laser radiation set the rules № 5804-91 .

They also set requirements for:

1. Devices and operation of lasers;
2. Industrial premises, placement of equipment and workplaces;
3. requirements for personnel;
4. Conditions of the industrial sphere;
5. Application of means of protection;
6. Medical control.

The brilliant prediction of A. Einstein, made by him back in 1917, about the possibility of induced light emission by atoms, was brilliantly confirmed almost half a century later when Soviet physicists N. G. Basov and A. M. Prokhorov created quantum generators. According to the English abbreviation, this device is also called a laser, and the radiation they create is called laser.

Where do we meet in everyday life with laser radiation? Nowadays, lasers are widely used - these are various fields of technology and medicine, as well as lighting effects in variety performances and shows. The beauty of iridescent and dancing laser beams has made them very attractive to home experimenters and manufacturers of laser gadgets. But how does laser radiation affect human health?

To deal with these issues, it is necessary to recall what laser radiation is. To do this, let's "fast forward" to a physics lesson in grade 10 and talk about light quanta.

What is laser radiation

Ordinary light is born in atoms. Laser light is the same. However, with other physical processes and as a result of exposure to an external electromagnetic field. Therefore, the laser radiation is forced (stimulated).

Laser radiation is electromagnetic waves propagating almost parallel to each other. Therefore, the laser beam has a sharp focus, an extremely small scattering angle and a very significant impact on the irradiated surface.

What is the difference between laser radiation and, for example, the radiation of an incandescent lamp? An incandescent lamp is a man-made light source that emits electromagnetic waves, unlike laser radiation, in a wide spectral range with a propagation angle of about 360 degrees.

The effect of laser radiation on the human body

The possibility of an extremely diverse application of quantum generators prompted specialists from various fields of medicine to come to grips with the impact of laser radiation on the human body. It was found that this type of radiation has the following properties:

The sequence of damage during the biological action of laser radiation is as follows:

• a sharp increase in temperature, accompanied by a burn;
• this is followed by effervescence of the interstitial as well as cellular fluid;
• the resulting steam creates tremendous pressure, culminating in an explosion and a shock wave that destroys the surrounding tissue.

At low and medium intensities of radiation, the skin is especially affected. With a stronger exposure, damage to the skin takes the form of edema, hemorrhage and dead areas. But the internal tissues undergo significant changes. Moreover, the greatest danger comes from direct and specularly reflected radiation. It also causes pathological changes in the work of the most important systems of the body.

Let us dwell in particular on the effect of laser radiation on the organs of vision.

Short pulses of radiation generated by a laser cause severe damage to the retina, cornea, iris and lens of the eye.

There are 3 reasons for this.

The characteristic symptoms of eye damage are spasms and swelling of the eyelids, eye pain, clouding and retinal hemorrhage. Retinal cells do not regenerate after damage.

The intensity of radiation that causes damage to the organs of vision is lower than the radiation that causes damage to the skin. Any infrared lasers, as well as devices that emit radiation in the visible spectrum with a power of more than 5 mW, can pose a danger.

Dependence of the influence of laser radiation on a person on its spectrum

laser radiation in medicine

Remarkable scientists from different countries, who worked on the creation of a quantum generator, could not even predict what wide application their offspring would find in various spheres of life. But each of these areas will require certain, specific wavelengths.

What does the wavelength of laser radiation depend on? It is determined by the nature, more precisely, by the electronic structure of the working fluid (the medium where this radiation is generated). There are various solid state and gas lasers. These miracle rays can belong to the ultraviolet, visible (usually red) and infrared parts of the spectrum. Their range is in the range from 180 nm. and up to 30 microns.

The nature of the impact of laser radiation on the human body largely depends on the wavelength. Our vision is about 30 times more sensitive to green than to red. Therefore, we will respond to the green laser more quickly. In this sense, it is safer than red.

Protection against laser radiation in production

There is a huge category of people whose professional activities are directly or indirectly related to quantum generators. For them, there are strict regulations and standards for protection against laser radiation. They include measures of general and individual protection, depending on the degree of danger that this laser device poses to all structures of the human body.

use of laser in production

In total, there are 4 hazard classes that the manufacturer must indicate. The danger to the human body is represented by lasers of classes 2,3 and 4.

Collective means of protection against laser radiation, these are protective screens and casings, light guides, television and telemetric methods of tracking, alarm and blocking systems, as well as fencing of an area with radiation exceeding the maximum permissible level.

Individual protection of employees is provided by a special set of clothing. To protect your eyes, it is mandatory to wear glasses with a special coating.

The best prevention of laser radiation is compliance with the rules of operation and protection, as well as timely medical examination.

Laser radiation protection for users of laser gadgets

Uncontrolled use of home-made lasers, lamps, light pointers, laser flashlights in everyday life poses a serious danger to others. To avoid tragic consequences, you should remember:

Quantum generators and any laser gadgets pose a potential threat to their owners and others. And only careful observance of security measures will allow you to enjoy these achievements without harm to yourself and your friends.