Places of production dust formation. Classification of dust by origin, dispersion, method of formation

Industrial dust occupies one of the first places among the causes of occupational pathology. This is due to the fact that a large amount of dust is generated during many production processes: during grinding, grinding, drilling, crushing, sifting, electric welding, blasting and transportation of dust-producing materials. High levels of air dust occur in mines, mines and during some agricultural work.

Effect of dust on the body depends mainly on chemical composition dust, the degree of dust in the air, the size and shape of dust particles.

The degree of air dustiness is expressed in milligrams of dust per 1 m3 of air. Clean air contains less than 1 mg of dust per m3. When there is a lot of dust, the dust content in the air reaches hundreds and even thousands of milligrams per 1 m3.

The size of dust particles affects the length of time they remain suspended in the air and the depth of penetration into the respiratory tract. Large dust particles, having a diameter of more than 10 (l), quickly, within a few minutes, fall out of the air. They linger in the upper respiratory tract and have a harmful effect on them. Enveloped in mucus, the retained dust particles are removed from the upper respiratory tract when sneezing and coughing Some of the mucus is swallowed, and if the dust is poisonous, it can manifest its toxic properties by being absorbed through the mucous membrane of the digestive tract. Large dust particles that are less than 10 liters in size can float in the air for hours without falling out. They penetrate. through the respiratory tract to the alveoli of the lungs, causing pneumoconiosis - diseases based on pulmonary fibrosis and associated changes. Breathing through your mouth or breathing deeply during heavy physical work introduces more dust into your lungs.

Large solid dust particles with a diameter of more than 10 (.1, if there are sharp edges or jagged edges (glass, quartz, iron filings) can more seriously injure the mucous membrane of the respiratory tract than soft dust particles with smooth, blunt edges (chalk, coal ) The shape of smaller particles does not matter in pathology.

The chemical composition of industrial dust is very diverse and in many cases it is this that determines the nature of the harmful effects of dust.

The effects of dust on the body are very diverse. Even indifferent dust, when it gets into the eye, has an irritating effect. This may be accompanied by the action of microorganisms, resulting in conjunctivitis and keratitis.

Indifferent dust, clogging the ducts of the sweat and sebaceous glands, disrupts sweating and plays a role in the occurrence of folliculitis, acne and pustular skin diseases. Irritating dust causes inflammatory skin diseases and the formation of ulcers (lime dust, sodium fluoride dust, arsenic dust, etc.).

With prolonged exposure to indifferent dust on the mucous membranes of the upper respiratory tract, hypertrophic catarrh (rhinitis, tracheitis, bronchitis) first develops, which turns into atrophic catarrh. Fluoride, chrome, lime and some other types of dust that have an irritating effect can cause ulceration of the nasal mucosa, nosebleeds and nasal pain.

Dust penetrating into the pulmonary alveoli, spreading through the lymphatic network in the lungs, causes the proliferation of connective tissue, i.e., pulmonary fibrosis. Subsequently, the connective tissue shrinks, scars form, compressing the vessels and small branches of the bronchial tree; individual sections of the lungs collapse. As a result, the main function of the lungs is disrupted - gas exchange and blood circulation in the pulmonary circle. The symptoms of chronic bronchitis include shortness of breath, cardiac failure, and decreased performance.

The most severe type of pneumoconiosis is s and l and goats , caused by inhalation of quartz dust containing free silicon dioxide in industrial conditions (mines, sand casting cleaning, etc.). At first, quartz dust acts mechanically, and then, as the silicon dioxide dissolves, it acts chemically. In silicosis, in addition to fibrosis, there is a breakdown of lung tissue with the formation of cavities, which leads to hemoptysis. Silicosis is often complicated by pulmonary tuberculosis. Silicon dioxide dissolves very slowly. Therefore, even after stopping work, silicosis can progress for some time due to the continued dissolution of silicon dioxide previously deposited in the lungs. Silicosis affects not only the lungs, but also other organs. Silicosis develops only after several years of inhaling dust.

In addition to silicosis, pneumoconiosis is known, caused by dust from coal, asbestos, iron and other substances. They are called anthracose, asbestosis, siderosis . Apart from asbestosis, their clinical course is much milder than silicosis. For example, anthracosis is a slow and relatively benign disease, rarely complicated by tuberculosis. Apparently, the severity of anthracosis depends on the amount of silicon admixture in coal.

Dust from hemp, flax, flour, grain, cotton and a number of other substances has allergenic properties, and in persons sensitive to it can cause conjunctivitis, rhinitis and asthmatic attacks of allergic origin. Dust containing toxic substances causes industrial poisoning; dust mixed with radioactive substances leads to radiation sickness; Infected dust can cause tuberculosis, actinomycosis, anthrax, fungal and other infectious diseases.

Fighting dust and preventing dust pathology are a major occupational health concern. According to hygienic standards, the content of dust (non-toxic) in the air production premises should not exceed 10 mg per 1 m3 if it contains less than 10% silicon impurity, and not exceed 2 mg if the dust contains more than 10% silicon.

In a number of industries, it is possible to get rid of dust by changing production technology, for example, instead of cleaning castings with a sandblaster, many plants and factories now clean them using a strong jet of water and shot. In other cases, a significant effect is achieved by replacing dry methods of work with wet ones, for example, irrigation of broken ore or gas and dust clouds after an explosion, wet drilling in mines and mines, and wet grinding of products. The introduction of wet drilling sharply reduced the incidence of silicosis among mine workers. In all cases, processes associated with the generation of dust or the transportation of dust-producing materials should be sealed and mechanized whenever possible. Places of dust formation are covered as much as possible with casings connected to exhaust ventilation ducts. Large quantity dust settles on the floor of production premises. Regular cleaning of the premises using a wet method or vacuum cleaners can prevent the secondary suspension of dust particles in the indoor air.

If the listed measures do not give the desired effect or are not applicable to this production, then we have to resort to measures personal protection. Anti-dust goggles are used to protect the eyes; to protect the respiratory tract - cotton gauze bandages or dust respirators, in which dust is retained on a paper or asbestos filter; to protect the skin - dust overalls. Workwear and underwear must be washed regularly, especially if the dust is irritating. After work, you should take a shower. In industries where dust may have a harmful effect on workers, especially quartz dust, medical examinations of workers are systematically carried out with chest x-rays to identify the early stages of diseases. Chronic respiratory diseases are the main contraindications for employment in which dust may affect the body.

64. THE CONCEPT OF OCCUPATIONAL POISONS AND OCCUPATIONAL POISONING. GENERAL REGULARITIES OF ACTION OF INDUSTRIAL POISONS. ACUTE AND CHRONIC POISONING. PREVENTION MEASURES.

TO industrial poisons include substances that, penetrating into the body in relatively small quantities, cause disruption of normal functioning or a painful condition - poisoning. Poisoning caused by poisons affecting the body in industrial conditions is called industrial, or occupational, poisoning. The effect of industrial poisons on the body is determined by: the toxicological characteristics of the toxic substance; the physical state of the poison and the ways it affects the body; concentration of poison in the air; the amount of poison resorbed by the body; duration of action. The severity of the work being performed matters, since the amount of inhaled air depends on it. The effect of poisons also depends on the body’s defenses. Overwork, irrational litany, and alcoholism increase intoxication. Industrial poisons can be in liquid, dusty, gaseous and vaporous states. Gaseous and vaporous poisons affect the body primarily through the respiratory tract. This route is the most dangerous, since the respiratory tract is difficult to protect from air contaminated with poisons, and due to the large surface of the pulmonary alveoli, the poison is quickly absorbed into the blood. Some gas and vapor poisons have a local irritant effect on the mucous membranes of the upper respiratory tract, the conjunctiva of the eyes and on the skin, especially if it is wet from sweat. Dust-like poisons act in the same ways as gaseous ones, but can penetrate the body through the digestive tract. Liquid poisons act primarily on the outer integument of the body. Those of them that are highly soluble in fats are able to penetrate into the bloodstream through intact skin (benzene, nitrobenzene, gasoline, tetraethyl lead).

Russia has adopted an official classification of the hazards of harmful substances

According to the degree of impact on the body, harmful substances are divided into 4 hazard classes :

1st - substances are extremely dangerous

2nd - highly hazardous substances

3rd - moderately hazardous substances

4th - low-hazard substances

Hazard indicators are divided into two groups. The first group includes indicators of potential danger - the volatility of the substance (or its derivative - the coefficient of possibility of inhalation poisoning (CVIO), equal to the ratio of volatility to toxicity during inhalation under standard conditions: 20 ° C, exposure - 2 hours, mice), solubility in water and fats and others (for example, aerosol dispersion). These properties determine the possibility of poison entering the body through inhalation, contact with skin, etc.

Industrial poisons can be classified into two large groups: inorganic substances and organic .

The most common inorganic toxic substances include the following groups of poisons: halogens (chlorine, bromine, etc.), sulfur compounds (hydrogen sulfide, sulfur dioxide, etc.), nitrogen compounds (ammonia, nitrogen oxides, etc.), phosphorus and its compounds (hydrogen phosphide, etc.), arsenic and its compounds (arsenous hydrogen, etc.), carbon compounds (carbon monoxide, etc.), cyanide compounds (hydrogen cyanide, cyanide salts, etc.), heavy and rare metals (lead , mercury, manganese, zinc, cobalt, chromium, vanadium and many others).

The most common organic substances include: aromatic hydrocarbons (benzene, toluene, xylene), their chlorinated and nitroamino derivatives (chlorobenzene, nitrobenzene, aniline, etc.), fatty hydrocarbons (gasoline, etc.), chlorinated fatty hydrocarbons (carbon tetrachloride , dichloroethane, etc.), fatty alcohols (methyl, ethyl, etc.), ethers, aldehydes, ketones, acid esters, heterocyclic compounds (furfural, etc.), terpenes (turpentine, etc.).

Industrial poisoning can be acute or chronic. Acute poisoning - those that occur under the influence of poison for no more than one work shift. Large doses of poison enter the body. Chronic poisoning arise as a result of prolonged action on the body of small quantities of toxic substances. These poisonings develop gradually, over early stages they are difficult to recognize because their symptoms are not very specific: malaise, increased fatigue, impaired appetite and sleep, anemia, weakened resistance to external influences.

For prevention of industrial poisonings the most radical is the complete elimination of poison from production or its replacement with less toxic compounds. In the production of mirrors, poisonous mercury is replaced by silver; the highly toxic solvent benzene is replaced by xylene or toluene. Great value gains mechanization, automation and thorough sealing production processes. To remove toxic gases and dust directly from the places where they are released, local exhaust ventilation (fume hoods, side exhausts) is used.

In necessary cases, local ventilation is supplemented with general ventilation. Processes associated with environmental pollution with toxic substances are carried out in isolated rooms. Before lowering workers into confined spaces - tanks, fermentation tanks, sewer wells, in which gases may accumulate, it is necessary to check the cleanliness of the air using indicator papers or a biological sample (lower the animal). The work must be done together. One worker remains outside and, if necessary, can extract the victim using a rope tied to a rescue belt.

Industrial dust is the name given to hovering in the air of a work area and slowly settling solid particles ranging in size from several tens to fractions of a micrometer. Dust is an aerosol in which air is the dispersion medium and solid particles are the dispersed phase.

The number of production processes in which intense dust emissions can occur is extremely large. The most dust-hazardous are many operations in the mining and coal industries, in mechanical engineering (electric welding, iron, copper and steel foundries, especially chipping and grinding), in the porcelain and earthenware, textile, flour-grinding industries, etc.

Dust classification

Industrial dust is classified according to the method of formation, chemical composition and size of dust particles.

By method of education:

1) disintegration aerosol, when dust is formed due to mechanical action on a solid substance (crushing, abrasion);

2) condensation aerosol formed from vapors of a substance during their cooling (electric welding aerosol, vapors of zinc oxide, iron, etc.).

By chemical composition:

1) organic:

a) vegetable (grain, flour, cotton, etc.);

b) animal (wool, hair, leather, bone, etc.);

c) protein (production of protein-vitamin concentrates - BVK).

2) inorganic:

a) mineral (silica, silicate, etc.);

b) metal (dust of iron, zinc, lead, etc.);

3) mixed:

a) mineral-metallic (a mixture of iron dust and silicon compounds; quartz and coal, etc.);

b) a mixture of organic and inorganic (dust of cereals and soil, cotton and sand, etc.).

By dispersion:

a) visible - the size of dust particles is over 10 microns, quickly falls out of the air;

b) microscopic - the size of dust particles is from 10 to 0.25 microns, slowly falls out of the air;

c) ultramicroscopic - the size of dust particles is less than 0.25 microns, floats in the air for a long time, obeying the laws of Brownian motion.

Diseases caused by dust

Dust can have different effects on the body: irritating, allergenic, fibrogenic, toxic.

In industrial conditions, dust can lead to the development of occupational diseases: pneumoconiosis, dust bronchitis, bronchial asthma. Local lesions may also occur: dermatoses, acne, asbestos warts, conjunctivitis, rhinitis. Some types of dust are carcinogenic (asbestos). Systematic work with dust can lead to an increased incidence of workers with temporary disabilities (colds, bronchitis, pneumonia, tuberculosis, etc.), which is associated with a decrease in the overall reactivity of the body.

Quartz-containing dusts, disintegration aerosols with dust particle sizes up to 5 microns (fractions of 1-2 microns are especially dangerous) and condensation aerosols with particles less than 0.3-0.4 microns have the greatest fibrogenic activity. For the development of dust bronchitis, particles larger than 5 microns are of primary importance.

An additional factor determining the pathological effect of dust is the shape of dust particles. Plate-shaped particles (mica, shale and some others) remain suspended in the air longer, while elongated and spindle-shaped particles (asbestos, etc.) penetrate into the deep parts of the respiratory tract and cause injury.

Quickly dissolving dusts are easily removed and have a weak pathological effect. Poorly soluble dusts linger for a long time in respiratory tract and have a more pronounced effect.

In particular, quartz-containing dust lingers in the respiratory tract for a long time and slowly dissolves in biological media, forming silicic acid, which is one of the leading factors in the development of silicosis.

Importance is given to the electrical charge of dust particles, which is important for the persistence of the aerosol.

A number of dusts have adsorption properties; dust particles are capable of carrying gas molecules (CO, CO2, methane), which can be a source of intoxication.

Dust can also be a carrier of microbes, spores, and helminth eggs.

To assess dust content, the weight method is used. The mass of dust is expressed in milligrams per 1 m3 of air (mg/m3).

General information

Industrial dust is one of the most common occupational hazards, which can cause dust diseases, which rank first among occupational diseases. The formation of dust and its release into the air of the working area occurs in many industries:

• in the mining and coal industries - when drilling rock, blasting, sorting, grinding;
• in mechanical engineering - during cleaning, cutting off castings, grinding, polishing products; metallurgy and chemistry - when performing pyrometallurgical processes of smelting metals and smelting various mineral materials;
• at textile enterprises - during cleaning and sorting wool, cotton, spinning, weaving, etc.

Industrial dust is finely divided solid particles that are suspended in the air of working premises, i.e. in the form of an aerosol.

Based on their origin, dust can be divided into organic (plant, animal, artificial), inorganic (metallic, mineral), and mixed.

Based on the method of formation, a distinction is made between disintegration aerosol (during mechanical grinding of solid materials) and condensation aerosol (during the evaporation and subsequent condensation of metal and non-metal vapors in the air).

According to dispersion - visible (sizes of dust particles are more than 10 microns), microscopic (sizes from 10 to 0.25 microns), ultramicroscopic (sizes less than 0.25 microns).

When assessing the effect of dust on the body, the shape of the particles, their hardness, sharpness, and fibrousness are of particular importance. The shape of dust particles, for example, influences their behavior in the air, speeding up (rounded) or slowing down (fibrous, plate-shaped) settling. The specific surface area (cm 2 /g) of dust is also important, since their chemical activity towards the body depends on the total surface area. Burnt products - expanded clay, expanded - perlite and vermiculite, having a surface 0.25 - 3 times larger than the raw materials used for their production (with a slight increase in silica content), have a more pronounced fibrogenic effect on lung tissue. The toxic effect of dust largely depends on the chemical nature of the dust and its concentration in the air of the working area. Soluble dusts, lingering in the respiratory tract, are absorbed, enter the bloodstream and their subsequent effect on the body depends on the chemical composition of the dust. For example, sugar dust is harmless, but dust from metals such as lead and zinc has a toxic effect on the body.

The chemical composition of dust, which largely determines the nature and degree of occupational dust pathology, depends on the type and composition of the material being processed, the method and technology of its processing. It is very important to determine silicon dioxide in dust, which is in connection (complex) with various compounds. In some cases, a slight admixture of some aggressive chemical compound changes its direction due to the action of dust: thus, hexavalent chromium found in domestic cements in an amount of up to 0.001% has a pronounced allergic effect.

In some cases, the deposition process and, consequently, the time they remain in the air depend on the electrical properties of dust particles. With opposite charges, dust particles are attracted to each other and quickly settle. With the same charge, dust particles, repelling one another, can remain in the air for a long time.

Dust can be a carrier of microbes, mites, helminth eggs, etc.

Effect on the body

Under the influence of dust, both specific and nonspecific diseases can develop. A specific pathology manifests itself in the form of pneumoconiosis - fibrosis of lung tissue. Pneumoconiosis is classified as follows:

• silicosis is a characteristic form of pneumoconiosis that occurs under the influence of free silicon dioxide dust;
• silicatosis - pneumoconiosis that occurs when inhaling dust from silicic acid salts (the most common type of silicatosis is asbestosis, cementosis, talcosis, etc.);
• metalloconiosis (berylliosis, etc.), carboconiosis (anithracosis, etc.);
• pneumoconiosis from mixed dust, from organic dust (byssiniosis, etc.).

The most dangerous disease is silicosis. It can develop among workers in the mining, coal, engineering industries, etc.

With silicosis, severe sclerotic changes are observed in the respiratory organs with simultaneous significant disturbances in the nervous, cardiovascular, digestive, and lymphatic systems.

Sclerotic changes in the lung tissue during silicosis lead to the development of emphysema, pulmonary insufficiency, damage to the bronchi, loss of their elasticity, bronchitis in some cases, bronchiectasis, etc. are observed.

According to the morphological picture in the lungs, two forms of silicosis are distinguished: nodular and diffuse sclerotic. Circulatory disorders develop in the pulmonary circulation, cardiopulmonary failure of the “pulmonary heart” type, etc. can be observed.

The secretory function of the gastrointestinal tract changes with inhibition of the activity of digestive enzymes.

Nonspecific diseases caused by exposure to industrial dust include pneumonia (manganese dust, slag dust), dust bronchitis, bronchial asthma (wood, flour dust), lesions of the nasal and nasopharyngeal mucosa (cement dust, chromium, etc.), conjunctivitis, skin lesions - warts, acne, ulcerations, eczema, dermatitis, etc. Some types of dust (asbestos, chromium) pose a carcinogenic hazard. Systematic work in conditions of exposure to dust causes an increased incidence of workers with temporary disability; this is due to a decrease in the protective immunobiological functions of the body. The effects of dust can be aggravated by heavy physical labor, cooling of the human body, and some toxic gases, which leads to a more rapid occurrence and increased severity of pneumoconiosis. Aerosols of some metals (vanadium, molybdenum, manganese, cadmium, etc.), dust of pesticides (hexachlorane, etc.) if not observed hygienic conditions labor in individual workers may cause occupational diseases. Preventive measures

Measures to limit the adverse effects of dust at work must be comprehensive and include technological, sanitary, medical, preventive and organizational measures.

Technical measures to combat dust are varied and depend on the properties of the dust, the nature technological process and type of equipment.

Eliminating dust formation in workplaces by changing production technology is the main way to prevent dust diseases. So, use in foundry injection molding made it possible to eliminate work with molding soil, and chemical methods of cleaning castings eliminated operations associated with dust formation.

IN engineering industry Replacing sandblasting of castings with shot blasting or hydrocleaning, or cleaning with acids completely eliminates the danger of silicosis. The possibility of silicosis occurring in the production of refractories has been significantly reduced by replacing quartzite and dinas raw materials with magnesite ones.

An effective measure to prevent pneumoconiosis is complex automation labor, in which equipment is controlled from remote panels and panels located in separate isolated rooms with favorable working conditions. Thus, at asphalt concrete and cement complex-automated enterprises, the dust content in such premises does not exceed the maximum permissible values.

In automated production facilities, where control panels are located in rooms with dust-producing equipment, dust control can only be effective with rationally arranged sanitary equipment for dust generation sources (shelter, ventilation).

When transporting, loading, unloading, and packaging dry, dusty materials, the use of pneumatic transport is very promising, when the movement of materials is carried out using compressed air through pipes, and the exit points of these materials should be equipped with aspiration followed by effective dust cleaning.

Drying processes for powder and paste-like materials should be carried out in closed continuous apparatus under vacuum - in drying drums, belt and spray dryers, roller, rake dryers, etc.

Humidifying raw materials, grinding the material in a wet state or supplying steam to the grinding zone, briquetting, granulating dusty materials lead to a significant reduction in air dust in the working area. The replacement of dry processing with wet processing led to the complete elimination of dust in the air in the preparatory workshops for the production of expanded clay.

To remove dust, it is necessary to use mechanical local exhaust ventilation (casings, fume hoods, and in some cases side exhaust). Basic hygienic requirements for local exhaust ventilation - complete covering of the place of dust formation and maintaining sufficient air speeds in the working sections and leaks of the casings (depending on the type of dust - at least 0.7-1.5 m/s). The air must be cleared of dust before being released into the atmosphere.

The complex of sanitary facilities should include rooms for storing and recharging respirators, and for cleaning dust from work clothes.

Treatment and preventive measures include the organization and conduct of preliminary and periodic medical examinations, the use of inhalers for the prevention and treatment of the upper respiratory tract (alkaline inhalations), fotariums for ultraviolet irradiation. Dust respirators can be recommended. At certain types work (sandblasting work), it is recommended to use helmets or suits with clean air supplied to the worker’s breathing zone.

The collection of tiny solid particles formed during the production process and suspended in the air of the working area is calledindustrial dust.

Industrial dust has an adverse effect on the body of workers.

There are several classifications of industrial dust.

Dust is divided

A) by origin , to:

- organic(plant, animal, polymer);

- inorganic(mineral, metal);

- mixed.

b) by place of education to:

- disintegration aerosols, formed during grinding and processing of solids;

- condensation aerosols, resulting from the condensation of metal and non-metal vapors (slag).

V) by dispersion to:

- visible(particles larger than 10 microns);

- microscopic(from 0.25 to 10 microns);

- ultramicroscopic(less than 0.25 microns).

G) by the nature of the effect on the body :

- toxic ( manganese, lead, arsenic)

- annoying(limestone, alkaline, etc.);

- infectious(microorganisms, spores, etc.);

- allergic(wool, synthetic, etc.);

- carcinogenic(soot, etc.);

- pneumoconiotic(causing specific fibrosis of lung tissue).

Toxicity and solubility of dust.

Toxic and good soluble dust penetrates the body faster and causes acute poisoning (manganese, lead, arsenic dust) than insoluble , leading only tolocal mechanical damage to lung tissue.

Vice versa, solubility non-toxic dust is favorable, since in a dissolved state “the substance is easily eliminated from the body without any consequences.

Physico-chemical properties of dust.

§ Dust grains smaller than 0.25 microns practically do not settle and are constantly in the air in Brownian motion.

§ Dust from particles less than 5 microns most dangerous, because it can penetrate into the deep parts of the lungs up to the alveoli and linger there.

It is estimated that about 10% of inhaled dust particles reach the alveoli, and 15% is ingested with saliva.

Dust charge value.

§ Charged particles are 28 times more actively retained in the respiratory tract and are more intensively phagocytosed.

§ Likely charged particles remain in the air of the working area longer than oppositely charged ones, which agglomerate and settle faster.

Industrial dust causes the development of various diseases, primarily:

§ diseases of the skin and mucous membranes (pustular skin diseases, dermatitis, conjunctivitis, etc.),

§ nonspecific respiratory diseases (rhinitis, pharyngitis, dust bronchitis, pneumonia),

§ diseases of the skin and respiratory system of an allergic nature (allergic dermatitis, eczema, asthmatic bronchitis, bronchial asthma),

§ occupational poisoning (from exposure to toxic dust),

§ oncological diseases (from exposure to carcinogenic dust, such as soot, asbestos),

§ pneumoconiosis (from exposure to fibrogenic dust).

Specific occupational dust diseases.

The most important among them are pneumoconiosis, chronic lung diseases resulting from prolonged exposure to industrial dust of a certain composition.

Pneumoconiosis develops in workers engaged in

In underground work,

Concentrating factories,

In the metalworking industry (chopping, molding, electric welders);

Workers at asbestos mining enterprises, etc.

Pneumoconiosis is a common disease and occurs through 1-10 years work in highly dusty conditions.

There are five groups of pneumoconiosis:

I. Caused by mineral dust :

Silicosis;

Silicates (asbestosis, talcosis, kaolinosis, olivinosis, mulitosis, cementosis, etc.).

II. Caused by metal dust :

Siderosis;

Aluminosis;

Beryllium;

Baritosis;

Manganoconiosis, etc.

III. Caused by carbonaceous dust :

Anthracosis;

Graphitosis, etc.

IV. Caused by organic dust :

Byssinosis (from cotton and flax dust);

Bagassosis (from sugar cane dust);

Farmer's lung (from agricultural dust containing fungi).

V. Caused by mixed dust :

Silico-asbestosis;

Silico-anthracosis, etc.

The greatest danger, due to its widespread and irreversible course, is silicosis (dust fibrosis , caused by inhalation of free dustsilicon dioxide).

Silicosis refers to one of the most important sections of occupational pathology, since it affects workers in a wide variety of industries.

The fight against silicosis is one of the main tasks in the problem of occupational health.

Silicosisusually develops after 5-10 years working in dusty conditions, however, in some cases, the disease can be observed for short periods of time.

According to its course, silicosis is divided into three stages.

I. The first stage is characterized by complaints of chest pain, shortness of breath with great physical exertion, and a slight dry cough. X-ray examination shows increased shadowing at the roots of the lungs and shadows of the lymph nodes, increased pulmonary pattern, the appearance of cords and a looped network, the presence of single nodules with a diameter of no more than 2 mm, mainly near the roots of the lungs. Basal emphysema cannot be excluded.

II. The second stage is characterized by greater severity of the above symptoms, an increase in the number and size of nodules, which are already found in the peripheral parts of the lungs. If silicosis develops slowly, without the formation of nodules, in the form of diffuse interstitial sclerosis of the lungs, then along with an intensification of the pulmonary pattern and expansion of the roots of the lungs, symmetrically scattered shadows in the form of cells, cords and spots of various shapes are noted. .Patients often complain of shortness of breath with moderate physical exertion or even at rest, and constant chest pain. Cough is dry or with phlegm. Emphysema is significantly pronounced.

III. In the third stage, radiographs reveal merging and fused large nodules, their clusters and massive fibrous areas. Dense cords going into different directions, predominantly downward, limit the mobility of the diaphragm. In stage III, functional impairments are clearly expressed:

Increased breathing at rest;

Pathological reaction to exercise testing;

Decreased vital capacity of the lungs.

Silicosisis a progressive disease.

The lowest stage, as a rule, passes into the next, the result is pulmonary failure, development of cor pulmonale, its decompensation and death of the patient.

It must be remembered that the development of silicosis continues, even if the patient has stopped working in an industry associated with dust, the disease may develop after stopping work.

Such cases, however, are characterized by slower progression (up to 10 years).

One of the properties of silicosis is a predisposition to the development pulmonary tuberculosis.

The more severe the silicosis, the more often it becomes complicated (the first stage - in 15-20% of cases, the second - in 30, the third - in 80% of cases).

It's important to note that silicosis is relatively rarely complicated by lung and bronchial cancer.

Most often, malignant neoplasms of the lungs occur in asbestosis And berylliose.

Prevention of dust diseases.

Prevention of occupational dust diseases includes:

1. hygienic standardization;

2. technological measures;

3. sanitary and hygienic measures;

4. individual means protection;

Industrial dust (or aerosols) are small solid particles of organic or mineral origin that are in the air of a work area and gradually settle. The size of one speck of dust can reach from 0.0001 to 0.1 mm in diameter.

Manufacturing operations that generate dust are very diverse. These include the process of crushing and grinding solids, sifting, drying, grinding, polishing various surfaces, and working with bulk materials. The dust released during these operations, according to the method of formation, belongs to the category of disintegration aerosols. Therefore, industries with intense dust generation include enterprises in the mining, coal, porcelain and earthenware, textile and flour milling industries.

Dust can also form during the melting and sublimation of some substance. As a result, vapors of this substance will be released, which, when air interacts with them, will begin to condense into small solid particles. According to the method of formation, such dust belongs to condensation aerosols.

Types of dust

There are so many types of industrial dust that it became necessary to classify it. The classification according to the method of aerosol formation is generally accepted.

• 1. Organic:
  • · vegetable (grain, etc.);
  • · animal (wool, etc.);
  • · protein (production of protein-vitamin concentrates).
• 2. Inorganic:
  • · mineral (silica, etc.);
  • metal (iron dust, etc.);
• 3. Mixed:
  • · mineral-metallic (a mixture of iron dust and silicon compounds, etc.);
  • · a mixture of organic and inorganic (dust from cereals and soil, etc.).

There is also a classification of dust by dispersion:

• 1. Visible (?10 µm);
• 2. Microscopic (from 10 to 0.25 microns);
• 3. Ultramicroscopic (? 0.25 microns).

By origin, dust is divided into:

• 1. Soluble (sugar, etc.);
• 2. Insoluble (bleach dust).