The question of the maximum allowable content dust In the air of work premises is important. The most correct method for determining the permissible concentrations of air dusting can be considered to be based on a comparison of long dynamic observations on the dust pathology of various professional groups and dusting of the external environment in which these groups work. The level of dusting, in which specific dust pathology is not noted, could be considered as extremely permissible. In this principle, the most allowed concentration in 1-2 mg / m3 recommended by various researchers is based on all types of dust with a significant content of quartz (quartz dust, sand, sandstone, granite, etc.) and dust asbestos.
In relation to other types non-toxic dust The maximum allowable content of it in the working area may be increased depending on the characteristics of the dust - its chemical composition, form, consistency and other properties.
Our legislation provides forcontaining quartz over 10%, an extremely permissible concentration of 2 mg / m3, for other types of non-toxic dust - up to 10 mg / m3. In accordance with the instructions shown in H 101-54, the maximum permissible concentrations of dust content in the air of the working area are established by industry in relation to individual manufacturing processes in coordination with the main state sanitary inspection of the Ministry of Health.
Basic eventsWarning in the air of the production premises of dust is rationalizing the technological process and equipment that excludes the possibility of dust formation, mechanization and automation of production, ventilation.
Of great importance is in particular pneumatic transportWidely used in preparatory workshops cotton factories, cement, tobacco, woodwork and some other industries. In the figure, as an example, the grinding scheme and the movement of bulk substances using vacuum pneumatics are shown. Ventilation devices on mill aggregates are significantly less effective.
A number of finished products can be issued not in powders, and in the form of paste (dyes) or tablets (white soot) than completely or largely eliminate dusting.
In foundry shops significant hygienic effect Provided when replacing sandblasting injection molding with hydrotreatment (jet of water under the addition of up to 100 atm. Peskohydrochimy (stream of wet sand) or when the sand is replaced. In the same workshops, the decline in dusty is achieved by applying the pneumatic transport of the ground, mechanization and automation of molding processes and knocked out sand shapes. , pride (ripping) casting.
On the image showing Device of hydraulicization during transport of dusting materials. Water sprayed from nozzles. In the mining and coal industry, the use of water in order to reduce the dustiness of the air is, according to the current rules, mandatory for all those under which significant dusting occurs. Such works include drilling with pneumatic hammers, wastewater treatment, and so on. However, the use of wet processing methods with water is usually unable to achieve the necessary efficiency of dedust. This is especially true of suspended in the air the most harmful small dusting up to 3-5 U.
Insufficient efficiency Dusting in wet work methods depends primarily from poor wetting water of dust, especially small. To enhance the efficiency of dedusting in these, cases in the mining and coal industry, small amounts (0.1-0.25%) of substances increasing wettance are added to the water. These wetting substances reduce the surface tension of water at the border with air. In addition, wethers have the ability to be adsorbed from an aqueous solution on solid surfaces.
Raising dusty water ability Under the action of small additions of wethers is connected, as Acad indicates. P. A. Rebelder, precisely with these two properties. A variety of organic products are proposed as wetters - soylonaf, contact Petrova, Sulfanol, DB, OP-7, OP-10, sulphite-alcohol bard (wetting agent with. B.) And others. Soylonaf is a by-product of oil refining; It consists of sodium salts of naphthenic acids, mineral oil and water. Contact of Petrov is obtained when cleaning solar and spindle oils with sulfuric acid.
Wetting action remote Contacts in the amount of up to 50% sulfonic acid - sulfanol mixture of sodium salts of alkylbenzenesulfonates. DB μi of polyethylene glycol monoalkylphenyl ethers; Product processing butylphenols by ethylene oxide. OP-7 and OP-10 - the chemical composition is close to the wet dB; Treatment products of high molecular weight alkylphenols with ethylene oxide. Unlike dB, the OP-7 wetter has an unpleasant smell of rot. OP-10 has this smell to a lesser extent. Sulftive-alcohol bard (wetter with. S. B.) - waste in the production of cellulose.
The composition is wetting additives To water, it is necessary to select in each case, taking into account the mineralogical composition of the rock, water rigidity, other local conditions and check both in the laboratory and the production. In particular, the soaps and other soaps in a tight iodine lose effectiveness under the influence of calcium and magnesium precipitation. With the right selection of wethers, their addition to water gives a significant effect, especially with respect to reducing the number of small dust. In the mining industry, the best results are obtained with a wetting agent of dB. Systems of general exhaust ventilation in the fight against dustiness are ineffective.
Considering the precipitation process dust On the floor, walls and equipment, it is necessary to carry out regular cleaning of work premises by distributing and wiping the dust with a wet moist method, and in some cases by pneumatic suction. It has the greater value than less dust particles and the more easier they can rise again into the air during cleaning indoors. It is important to remove dust that have seen on the instruments of central heating radiators and pipes: with a vapor or water heating of medium or high pressure dust, settled on the instruments, can burn and become a source of air pollution.
In cities, the air is very much polluted by the harmful emissions of vehicles and industrial enterprises emitting a whole range of substances, each of which with varying degrees of intensity adversely affects human health.
For all pollutants, there are MPC standards (maximum permissible concentrations) of substances in the air. In compliance with these rules, special authorities should follow (in Moscow it is the GPU "Mosekomonitoring") and in the case of the systematic violations to impose certain sanctions: from a fine to closure of the enterprise.
This page provides brief characteristics of some of the most common harmful substances emitted into the air by road and industrial enterprises.
Hazard class of harmful substances - The conditional value intended for a simplified classification of potentially hazardous substances.
Standard GOST 12.1.007-76 "Classification of harmful substances and general security requirements" Sets the following features to determine hazard class harmful substances:
According to the degree of impact on the body, harmful substances are divided into four classes of danger:
I substances are extremely dangerous
High substances II
III substance moderately dangerous
IV substances are low hazard
PDK - The maximum permissible concentration of pollutant in atmospheric air is a concentration that does not have direct or indirect adverse effects on a real or future generation, which does not reduce human health, without worsering his well-being and sanitary living conditions.
PDKSS - Maximum permissible average daily concentration of chemical in the air of settlements, mg / m3. This concentration should not have a direct or indirect harmful effect on a person with an indefinitely debt (years) inhalation.
Characteristics of harmful substances.
Sulfuric anhydride (sulfur dioxide) SO2
Hazard class - 3
PDKSS - 0.05
PDKMR - 0.5
Colorless gas with a characteristic sharp smell. Toxic.
In the light cases of poisoning with sulfur anhydride appear cough, runny nose, tearing, dryness in throat, huskiness, chest pain; with acute poisoning of moderate severity, in addition, headache, dizziness, general weakness, pain in the opposite region; When inspection - signs of chemical burns of the mucous membranes of the respiratory tract.
Prolonged impact of sulfuric anhydride can cause chronic poisoning. It is manifested by atrophic rhinitis, dental damage, often exacerbating toxic bronchitis with the attacks of choking. Liver damage, blood system, the development of pneumosclerosis are possible.
Especially high sensitivity to sulfur dioxide is observed in people with chronic disorders of respiratory organs, with asthma.
Sulfur dioxide is formed using reserve fuels of fuel by the enterprises of the heat and power complex (fuel oil, coal, low quality gas) and emissions of diesel vehicles.
Nitrogen oxide (nitrogen oxide) NO.
Hazard Class -
PDKSS - 0.06.
PDKMR - 0,4.
Colorless gas with a weak sweet smell, known as "funny gas", because Significant quantities of it actively act on the nervous system. In a mixture with oxygen, used for anesthesia in light operations.
The compound has a positive biological effect. NO is an essential biological conductor capable of causing a large number of positive changes at the cellular level, which leads to an improvement in blood circulation, immune and nervous systems.
Nitrogen oxide is formed when burning coal, oil and gas. It is formed in the interaction of nitrogen N2 and oxygen O2 air at high temperature: the higher the temperature of the combustion of coal, oil and gas, the greater the nitrogen oxide is formed. Next, at a conventional temperature, NO is oxidized to NO2 which is already a harmful substance.
Nitrogen dioxide (nitrogen double-oxide) NO2
Hazard class - 2
PDKSS - 0.04.
PDKMR - 0.085
At high concentrations, brown gas with a stileanese smell. Acts as a sharp stimulus. However, with those concentrations that are present in the atmosphere, NO2 is rather a potential irritant and only potentially it can be compared with chronic pulmonary diseases. However, in children at the age of 2 -3, some increase in bronchitis diseases were observed.
Under the influence of solar radiation and in the presence of unburned hydrocarbons, nitrogen oxides react to the formation of photochemical smog.
Often, various nitrogen oxides, which are formed during the combustion of any types of fuel, are combined into one group "NOX". However, nitrogen dioxide NO2 is the greatest danger.
Carbon Oxide CO (carbon monoxide)
Hazard class - 4
PDKSS - 0.05
PDKMR - 0.15
Gas without color and smell. Toxic. With acute poisoning, headache, dizziness, nausea, weakness, shortness of breath, rapid pulse. It is possible to loss of consciousness, convulsions, coma, circulatory disruption and breathing.
In chronic poisoning, headaches appear, insomnia, there is an emotional instability, attention and memory will deteriorate. Organic lesions of the nervous system, vascular spasms
Carbon oxide is formed as a result of incomplete combustion of carbon in fuel. In particular, when combustion of carbon or compounds on its basis (for example, gasoline) under conditions of lack of oxygen. Such an education occurs in the furnace firebox when the furnace flap is too early (until the coal has not finally burned). Forming a carbon monoxide, due to its poisonousness, it causes physiological disorders ("Ugra") and even death, from here and one of the tanks - "Curmargin gas"
The main anthropogenic source of CO currently serves exhaust gases of internal combustion engines of cars. Carbon oxide is formed during the combustion of hydrocarbon fuel in internal combustion engines with insufficient temperatures or poor adjustment of the air supply system
Carbon dioxide (carbon dioxide) CO2
Colorless gas with a weak acid odor. Carbon dioxide is not toxic, but does not support breathing. Large concentration in the air causes suffocation. Causes hypoxia (duration of up to several days), headaches, dizziness, nausea (end 1.5 - 3%). At conc. Above 61% is lost performance, drowsiness, impaired breathing, cardiac activity, is dangerous for life.
CO2 absorbs the emitted earthly infrared rays and is one of the greenhouse gases, as a result of which participates in the process of global warming
Vanadium five-pointed V2O5.
Hazard class - 1
PDKSS - 0.002.
Poisonous. Causes irritation of the respiratory tract, pulmonary bleeding, dizziness, violation of the activity of the heart, kidney, etc. Carcinogen.
The compound is formed in small quantities when combing fuel oil.
Seroublerod (carbon disulfide) CS2, colorless liquid with an unpleasant odor.
Hazard class - 2
PDKSS - 0.005
PDKMR - 0.03
Couples of servo-carbon poisonous and very easily flammable. Acts on central and peripheric nervous systems, vessels, metabolic processes.
With light poisoning - a narcotic action, dizziness. In the poisoning of moderate gravity arises with a possible transition to whom. In chronic intoxication, nervously vascular disorders arise, impaired psyche, sleep, etc.
With long-term poisoning, encephalitis and polynevrit may occur. Recurreers can occur with the loss of consciousness, the oppression of breathing. When welcome, nausea, vomiting, abdominal pain occurs. When contacting the skin, hyperemia and chemical burns are observed.
Xylene (dimethylbenzene)
Hazard class - 3
PDKSS - 0,2
PDKMR - 0,2
Forms explosive steam-air mixtures.
Causes sharp and chronic damage to the hematopoietic organs, dystrophic changes in the liver and kidneys, during contact with skin - dermatitis.
Benzene
Hazard class - 2
PDKSS - 0,1
PDKMR - 1.5
Colorless bat with a kind of blurred smell.
Carcinogen.
With acute poisonings, there is a headache, gluing, nausea, vomiting, the excitation of a condensed state, a frequent pulse, a drop in blood pressure. In severe cases - cramps, loss of consciousness.
Chronic poisoning is manifested by blood change (violation of the functions of the bone marrow), dizziness, total weakness, sleep disorder, fast fatigue. In women - violation of menstrual function.
Benzpiren, Benz (a) Pyrene
Hazard class - 1
PDKSS - 0,01
It is formed during the combustion of hydrocarbon liquid, solid and gaseous fuels (to a lesser extent, rod combustion). It can appear in flue gases when burning any fuel with a lack of oxygen in separate combustion zones.
Benz (a) Pyrene is the most typical chemical carcinogen of the environment, it is dangerous for a person even at low concentration, since it has the property of bioaccumulation. Being chemically relatively stable, benz (a) Pyrene can long migrate from one objects to others. As a result, many objects and environmental processes themselves who do not have the ability to synthesize benz (a) pyrene, become its secondary sources. Benz (a) Pyrene also has a mutagenic effect.
Toluene (methylbenzene)
Hazard class - 3
PDKSS - 0.6.
PDKMR - 0.06.
Colorless combustible liquid.
The limits of the exploded mixture with air 1.3 - 7%.
Toluene (methylbenzene) is a strong toxic poison that affects the function of the body's blood formation, as well as its predecessor, benzene. Blood breeding manifests itself in cyanosis, hypoxia.
Toloole pairs can penetrate the intact skin and respiratory organs, cause the damage to the nervous system (inhibition, violations in the vestibular apparatus), including irreversible
Chlorine
Hazard class - 2
PDKSS - 0.03.
PDKMR - 0,1
Yellow-green gas with a sharp annoying smell. Annoying mucous membranes of the eyes and respiratory tract. A secondary infection is usually attached to the primary inflammatory processes. Acute poisoning develop almost indulgent. When inhalation of medium and low concentrations, constraints and pain in the chest, rapid breathing, turning into the eyes, tearing, increased blood leukocyte content, body temperature, etc. Bronchopneumonia, lung swelling, depressive state, cramps are possible. As long-term consequences, the catar of the upper respiratory tract is observed, bronchitis, pneumosclerosis, etc. Activation of tuberculosis is possible. With long-term inhalation of small concentrations, similar, but slowly developing forms of the disease are observed.
Chrome hexavalent
Hazard class - 1
PDKSS - 0.0015
PDKMR - 0.0015
Toxic. The initial forms of the disease are manifested by the feeling of dryness and pain in the nose, in the throat, the difficulty of breathing, cough, etc. With long-term contact, signs of chronic poisoning are developing: headache, weakness, dyspepsia, weight loss, etc. The functions of the stomach, penetration and pancreas are disturbed. Bronchitis, asthma, diffuse pneumosclerosis are possible. When exposed to the skin, dermatitis, eczemas may develop.
Chromium compounds possess carcinogenic effect.
Soot
Hazard class - 3
PDKSS - 0.5
PDKMR - 0.15
Dispersion carbon product non-ball combustion. Save particles do not interact with air oxygen and therefore removed only by coagulation and precipitation that go very slowly. Therefore, to preserve the cleanliness of the environment, you need very hard control over soot emissions.
Kantzpogen, contributes to the occurrence of the skin of the skin.
Ozone (o3)
Hazard class - 1
PDKSS - 0.03.
PDKMR - 0.16.
Explosive blue gas with a sharp characteristic odor. Kills microorganisms, therefore it is used for water purification and air (ozonation). However, only very small concentrations are permissible in the air. Ozone extremely poisonous (more than carbon monoxide gas).
Lead and its connections (except Tetraethylswin)
Hazard class - 1
PDKSS - 0.0003
Poaming, affects the centered unpellent system, even the small doses of lead cause lag in children in the mouth of intelligence. The damage to the nervous system is manifested by asthenia, with pronounced forms - encephalopathy, paralysis (mostly extensors of the brushes and fingers), polyneurism.
In chronic intoxication, the liver, cardiovascular system, violation of endocrine functions (for example, in women - miscarriages) are possible. The inhibition of immunobiological reactivity contributes to an increased overall morbidity. Conventional expressions are possible.
Lead affects the human nervous system, which leads to a decrease
Intellect causes a change in physical activity, coordination of hearing,
affects the cardiovascular system, leading to a heart disease.
This has a negative impact on the health of the population and in the first
The queue of children who are most susceptible to lead poisoning.
Carcinogen, Mutagen.
Tetroethylswin
Shove - 0.000003.
Gulf.
At temperatures above 77 ° C, explosive mixtures of par / air can be formed.
The substance annoys the eyes, skin, respiratory tract. The substance can have an effect on the central nervous system, leading to irritability, insomnia, heart disorders. Impact may cause clouded consciousness. The effects of high concentrations can cause death. The medical observation is shown.
With long-term or multiple exposure, a toxic effect on the reproductive function of a person may have a toxic effect.
Formaldehyde HCOH
Colorless gas with a sharp smell.
Toxic, has a negative effect on genetics, respiratory organs, vision and skin. It has a strong impact on the nervous system. Formaldehyde is listed in the carcinogenic substance.
The substance can have an action on the liver and kidney, leading to functional disorders
Apply formaldehyde in the manufacture of plastics, and the main part of formaldehyde is under the manufacture of chipboard and other chipstroke materials. In them, the phenol-formaldehyde resin is 6-18% of the mass of the chips.
Phenol
Phenol is a volatile agent with a characteristic sharp odor. Pair of his poisonous. If the phenol appears on the skin, it causes painful burns during acute poisoning - disruption of respiratory functions, CNS. In chronic poisoning - violation of liver and kidney functions
Selena dioxide
Hazard class - 1
PDKSS - 0.05
PDKMR - 0,1
The substance has a corrosive effect on the eyes of the skin and respiratory tract. Inhalation can cause pulmonary edema (see notes). The substance can have an effect on the eyes, leading to an allergo-like century reaction (red eyes). The medical observation is shown.
Repeated or longcoming can cause skin sensitization. The substance can have an effect on the respiratory tract and the gastrointestinal tract, the central nervous system and the liver, leading to the irritation of the nasopharynx, the gastrointestinal distress and the constant smell of garlic and the damage to the liver.
Hydrogen sulfide
Hazard class - 2
PDKMR - 0.008.
Colorless gas with smell of rotten eggs.
The substance annoys the eyes and respiratory tract. Inhalation of gas can cause swelling of the lungs. Fast evaporation of the fluid can cause frostbite. The substance may have an action on the central nervous system. Impact can cause loss of consciousness. Impact can cause death. Effects may be delayed.
Bromboenzene. C6H5Br.
Hazard class - 2
PDKSS - 0.03.
The substance irritates the skin. The ingestion of the liquid can cause aspiration in the lungs with the risk of the occurrence of chemical inflammation of the lungs. The substance may have an action on the nervous system.
Can have an action on the liver and kidney, leading to functional disorders
Methylmercaptan Ch3sh.
Hazard class - 2
PDKMR - 0.0001.
Colorless gas with a characteristic odor.
Heavy air gas. and can step on the ground; Perhaps fire is possible.
The substance annoys the eyes, skin and respiratory tract. Inhalation of gas can cause pulmonary edema. Fast evaporation of fluid can cause frostbite. The substance can have an action on the central nervous system, leading to breathing failure. Impact in a large dose may cause death.
Due to the strong unpleasant odor, methylmercaptan is used to add to harmful gases that are not smell to detect leakage.
Nitrobenzene
Hazard class - 4
PDKSS - 0.004.
PDKMR - 0,2
The substance may have an effect on blood cells, leading to the formation of methamoglobin. The impact may cause clouding consciousness. Effects may be delayed.
With prolonged exposure, it can have an effect on the blood formation organs and on the liver.
Ammonia
Ammonia NH3, hydrogen nitride (smell of ammonia alcohol), almost twice the easiest air
Hazard class - 2
PDKSS - 0.004.
PDKMR - 0,2
Colorless gas with a sharp stumble smell and caustic taste.
Poading, heavily irritates the mucous membranes.
In acute ammonia poisoning, eyes and respiratory tract are affected, with high concentrations, death is possible. Causes a strong cough, suffocation, with a high concentration of vapors - excitement, nonsense. When contacting the skin - burning pain, swelling, ezheg with bubbles. In chronic poisoning, disorder is observed, Qatar of the upper respiratory tract, weakening hearing.
A ammonia mixture with air is explosive.
Dust is the smallest particles of solids that are capable of being suspended for some time.
By influence on the body, dust can be toxic and non-toxic. Toxic refers to industrial poisons and acts similarly to toxic gases.
Under productive dust understands non-toxic dust. The main professional diseases in its action are pneumoconiosis, chronic bronchitis, diseases of the mucous membranes of respiratory tract and leather.
The most severe pneumoconiosis is caused by the action of silicon dioxide (SiO 2) - silicosis, coal dust - antisham, asbestos dust - asbestosis. Many of the dust of vegetable and animal origin has an allergenic effect (herbs, grains, flour, straw, etc.).
The danger of damage affects: particle form, dust dispersion, electrical, physicochemical properties, solubility.
Aerosols predominantly fibrogen action (APFD) (dust) - physical factorthese are the same chemicals found in nature or chemical synthesis obtained, but for their control, the method of weight (gravimetric) analysis is used.
Fibrogenicthis action of dust is called, in which the smallest of the connective tissue, which disrupts the normal structure and function of the organ.
UPFD are divided into:
High and moderately fibrogenic, with PDK ≤ 2 mg / m 3
Weak fibrogenic PDC ˃ 2 mg / m 3
UPFD is identified as harmful and (or) dangerous factors only in workplaces, in which:
Mining is carried out;
Enrichment;
Production and use in the process of dusting substances belonging to APFD;
Equipment is operated, the work on which is accompanied by the extraction of APFD (dust containing natural and artificial mineral fibers, coal dust):
GN 2.2.5.1313-03 "Maximum permissible concentrations (MPC) of harmful substances in the air of the working area" 2472 names, of which 125 of the APFD, Table. 4.10.
Table 4.10. PDC dust in the air of the working area
In the workplace, the concentration of dust must be measured in the respiratory zone (at an altitude of 1.5 m from the floor when working standing and 1.0 m - when working sitting). Sampling equipment is shown in Fig. 4.3.
1) 
2)
Fig.4. 3 Equipment for air sampling at APFD:
1- Air intake device, 2 - filters.
The impact of APFD on the body:
§ difficult to breathe, causes cough and sneezing;
§ Toxic dust can lead to poisoning, suffocation, etc.;
§ worsens visibility, leads to irritation of the mucous shell of the eye and elevated tear;
§ causes skin irritation;
§ If visibility worsening increases the risk of injury.
Calculation of dust load.At the evidence tothe conditions of labor in nonstationary workplaces and (or) with a direct contact of employees with AFFD during the working week, the working conditions of the expectancy of the dust load per year (Mon 1) are calculated, based on the expected actual number of workers shifts worked out in the impact of APFD:
PN 1 year \u003d to SS · N · Q ,
where: To CC- the actual medium-average concentration of dust in the employee's breathing zone, mg / m 3;
N. - the number of workers shifted in the calendar year under the impact of APFD;
Q. - the volume of pulmonary ventilation per shift, m 3.
The volume of pulmonary ventilation, which depends on the level of energy and, accordingly, categories of work (according to Sanpin 2.2.4.548-96) is:
The resulting value of Mon 1 is compared with the quantity of the CPN for the year (the total number of workers shifting a year N yearwhen exposed to an APFD at the level of the medium pdk, respectively
KPN 1 year \u003d PDC ss × n year × q.
According to the actual dust load of the control level (KPN 1, the working conditions refer to the permissible class of working conditions. The multiplicity of exceeding the control dust load indicates the class (subclass) of the working conditions according to Table 4.11.
Table 4.11. Classes of working conditions depending on the content in the air of the working area of \u200b\u200bthe UPFD, (the multiplicity of exceeding the PDC and KPN)
Production lighting
4.5.1 Lighting units
Illumination (E) - the surface density of the light flux, is defined as the ratio of the Luminous Flow DF to the area of \u200b\u200bthe illuminated surface (DS), the Light Unit - Suite (LC):
Background - This is a surface on which the object distorted. Under the object of distinction is understood as the minimum element of the subject matter under consideration. The background is characterized reflection coefficient (R) - the ability to reflect the light falling on it, it is defined as the ratio of the reflected light flux F OTP to the falling F Pad:
r \u003d F ONP / F Pad
The reflection coefficient varies from 0.02- black velvet to 0.95 mirrors. At R.< 0,2 фон считается темным, при r = 0,2 – 0,4 – средним; при r > 0.4 light.
The contrast of the object with the background (K) is characterized by the ratio of brightness or reflection coefficients of the object under consideration and the background. The contrast between the object and the background is determined by the formula:
K \u003d. =
where L o and l f;r O. and R F. - respectively brightness (L) and reflection coefficients (r) object and background.
The contrast is considered to be large at K\u003e 0.5, mean - with k \u003d 0.2-0.5 and small - with<0,2.
Pulsation coefficient (K n) - Changing the illumination of the surface due to periodic changes in the time of light flow of the light source:
k n \u003d [(e max - e min) / 2e cf] 100%
where E max, e min and e CP is the maximum, minimum and average illumination value for the period of oscillations; For gas-discharge lamps K n \u003d (25-65)%, for incandescent lamps - K n \u003d 7%, for halogen lamps - k n \u003d 1%.
Octoption rate (P 0) - Criterion for estimating the blinding action created by the lighting installation:
P 0 \u003d 1000 (V 1 / V 2 - 1)
where V 1 and V 2 is the visibility of the object of distinction, respectively, by shielded and disranged light source.
4.5.2 Production Lighting Systems
The lighting of industrial premises is divided into natural and artificial.
Daylight - side (single and bilateral) - through light openings in the outer walls; Upper - through light lights, openings in the roof and overlaps and combined - a combination of upper and lateral lighting.
Artificial lighting It may be common (uniform or localized) and combined (general and local).
According to functional purposes, artificial lighting is divided into working, emergency and special, which can be a security, duty, evacuation, erythene, bactericidal, etc.
Working light It is mandatory for all industrial premises.
Emergency lighting It is arranged to continue working in the premises where the disconnection of the working light can lead to accidents. The minimum illumination should be 5% of the normalized working light, but not less than 2 LCs.
Evacuation lighting - It is organized in places dangerous for the passage of people with the number of more than 50 people working. The minimum illumination on the floor should be in rooms at least 0.5 LCs, in open areas - at least 0.2 LC.
Security lighting It is arranged along the boundaries of territories protected by special staff. The smallest illumination is 0.5 lk ..
Signal lighting It is used to fix the boundaries of hazardous areas; It indicates the presence of danger or on the safe path of evacuation.
Bactericidal irradiation (Lighting) is created to disinfect air, drinking water, food. The greatest bactericidal ability is ultraviolet rays long in (254-257) Nm.
Erytheo irradiation It is created in the premises where there is not enough sunlight (Northern regions, underground structures). Maximum erythene effects have electromagnetic rays with a wavelength of 297 nm. They stimulate the metabolism, blood circulation, breathing and other organism functions.
Sources of artificial light serve incandescent lamps, luminescent and LED lamps.
4.5.3 Lighting rationing
Illumination is normalized SP 52.13330.2011."Natural and artificial lighting"; and Sanpin 2.2.1 / 2.1.1.1278-03"Hygienic requirements for natural, (Table 4.12 and 4.13). For artificial illumination, the normalized parameter is the minimum illumination (E min) on the working surface in the horizontal plane at a distance of 0.8 m from the floor.
All works are divided into VIII discharges, and I - V are divided into diodes. E Min is selected depending on the accuracy of the visual work, the reflection coefficient of the visual surface and contrast with the background.
Light measurements are made using luxury luxury, which have an error that is not more than 10%. It consists of a galvanometer and a photocell, Fig. 4.4.
When working in an open territory, only during the daytime, working conditions in the workplace in terms of the lighting of the working surface are admissible.
When the workplace is located in several workshes (indoors, in areas, in an open territory), the working conditions for labor to the class (subclass) of working conditions under the influence of the luminous medium is carried out with respect to the residence time in different roughing of formula (4.1):
Table 4.12. Normated indicators of natural, artificial and combined lighting of the main premises of the public building, as well as the accompanying industrial premises of the SP 52.13330.2011
| Premises | Working surface | Daylight | Combined lighting | Artificial lighting | ||||||||
| and plane | Keo,% | Keo,% | ||||||||||
| Normarization of Keo and illuminations (g - horizontal, in - vertical) and height of the plane above the floor, m | at the top or combined refreshment | with lateral refreshment | at the top or combine refreshment | with lateral lighting | Illumination, LK | Disconfigure disk, m, no more | Coefficient of lightening pulsations,%, no more | |||||
| when combined lighting | With general lighting | |||||||||||
| Total | from total | |||||||||||
| 1.Babinets, work rooms, offices, offices | Mr..8. | 3,0 | 1,0 | 1,8 | 0,6 | |||||||
| 2. Roadrooms and rooms design, drawing bureaus | Mr..8. | 4,0 | 1,5 | 2,4 | 0,9 | |||||||
| 3. Compound for photocopying | Mr..8. | - | - | - | - | - | - | |||||
| 4. Make-up, carpentry, repair shops | Mr..8. | - | - | 3,0 | 1,2 | 15/20 | ||||||
| 5. Assignments to work with displays and video terminals, halls of the computer | M-0.8 Monitor Screen: | 3,5 - | 1,2 - | 2,1 - | 0,7 - | - | - | |||||
| - | ||||||||||||
| Conference rooms, meeting rooms | Mr..8. | - | - | - | - | - | - | |||||
| Culuars (Foyer) | M-0,0 | - | - | - | - | - | - | - | ||||
| Laboratories | Mr..8. | 3,5 | 1,2 | 2,1 | 0,7 | |||||||
Fig.4.4. Luxmeters: 1- PCM, 2 - Testo - 540
Table 4.13. Conditioning working conditions in the class (subclass) working conditions when exposed to the luminous medium
where: UT. - working conditions expressed in points;
UT 1, UT 2, ..., UT N - working conditions in the 1st, 2nd, n.Both working areas, respectively, expressed in points relative to class (subclass) of labor conditions (permissible working conditions - 0 points; harmful working conditions (subclass 3.1) - 1 point; harmful working conditions (subclass 3.2) - 2 points);
t 1, T 2, T N - the relative time of stay (in the fractions of units) in the 1st,
2nd, n.work zones, respectively
Production noise
The frequency range of auditory perception by man of sound oscillations is ranging from 16 to 20,000 Hz.
Everyone unwanted sound sound is called noise.
Noise violates information, which affects mistakes and injuries. He causes fatigue.
The impact of noise is reflected, first of all, on the hearing organs. There are three forms of exposure - hearing fatigue, noise injury and professional hearing loss, which leads to a decrease in hearing up to its full loss.
At each point of the sound field, the pressure and speed of propagation varies in time. The difference between the instantaneous value of the pressure formed in the medium during sound passage ( R cf.) and atmospheric pressure ( R atm) Called sound pressure - denoted by the letter R Zv and is measured in Pascals (PA) (Fig. 4.5).
Fig. 4.5. Illustration of sound pressure
When the sound wave is propagated, energy is transferred. The average energy flow referred to the surface is normal to the direction of propagation of waves, is called sound intensity I (W / m 2) at this point.
Sound intensity is associated with sound pressure addiction
(4.2)
where ρ - medium density, kg / m 2;
from - Sound speed in this environment, m / s.
The magnitudes of the sound pressure and the intensity of the sound, with which you have to deal with, are widely limited. So, the minimum value of the intensity of the sound perceived by man at the frequency f \u003d 1000 Hz is equal to I O. \u003d 10 -12 W / m 2 called threshold hearingness. The maximum value is called threshold of pain and equal I Max\u003d 10 2 W / m 2. In this case, the sound pressure range varies from R O. \u003d 2 · 10 -5 pa R Max\u003d 2 · 10 2 PA.
In the practice of measurements, the absolute values \u200b\u200bof the intensity of sound and sound pressure do not use, and only the logarithmic (deciable) scale is used. This is caused by the following reasons:
First, the range of sound change and sound pressure is extremely wide, the normal human ear is not able to perceive minor changes in sound pressure.
Secondly, the human ear reaction to the different volume of sound is logarithmic. Therefore, Bal introduced an indicator of the level of intensity (sound pressure level), which is determined by the formula
(4.3)
where I is the intensity of sound on the threshold of hearingness (10-12 W / m 2).
If we substitute in formula (2) instead of I, the value of the intensity on the threshold of the pain sensation (I max \u003d 10 2 W / m 2), then we obtain the entire range of auditory perception (L I max, dB).
dB (4.4)
Since the intensity of sound is proportional to the square of the sound pressure, then:
Production noise is characterized spectrumconsisting of sound waves of different frequencies.
In the study of noise, the audible range of 16 Hz - 20 kHz is divided into frequency bands ( spectrum Noise) .
Frequency band, the upper bound of which exceeds the lower two times. f. 2 = 2 f. 1, called octava.
For a more detailed study of noise, sometimes used third battalies frequency bands for which f. 2 \u003d 2 1/3 · f. 1 = 1,26 f. 1
The octave and third-grade strip is usually set by the medium meterometric frequency: f cf \u003d. 
.
There is a standard range of middle-meter frequencies of octave bands, in which noise spectra are considered ( f. SG M in \u003d 31.5 Hz, f. SG MAX \u003d 8000 Hz), Table. 4.14.
By the nature of the spectrumnoises are divided on tonal (Separate tones are expressed in the spectrum) and broadband(with a continuous spectrum of more than one octave).
By temporary characteristic - permanent(the sound level for the working day changes no more than 5 dBA) and non-permanent (The sound level for the working day changes less than 5 dBA). Non-permanent, in turn, are divided into i oscillating in time, impulse and intermittent.
The human ear does not react to sounds with different frequencies. Ear sensitivity (volume) increases significantly at frequencies from 20 to 1000 Hz. The greatest sensitivity of the human ear has in the frequency range from 1000 Hz to 4000 Hz. 4.6.
Figure 4.6. Schedule of curves of equal volume: 1- Threshold of hearingness; 2 - threshold of pain; 3 - the area of \u200b\u200bspeech gears; 4- area of \u200b\u200bmusical gear.
To estimate the volume of noise on different frequencies, used standard frequency characteristic Aapproaching the sensitivity of the human ear. At the same time used amendments on scale a(Table 4.15).
Table 4.15. Standard values \u200b\u200bof the correction for frequency correction on the scale A.
| Frequency | 31,5 | |||||||||
| Correction ΔL A, DBA | 26,3 | 16,1 | 8,6 | 3,2 | -1,2 | -1,0 | 1,1 |
Corrected on the scale and the level of sound pressure, dBA in the i-th octave strip is calculated as:
ΔL A I. = L i - Δl A I (4)
The total noise level (volume level or sound level) with a complex spectral composition is determined by the level of sound in all octave bands by the formula:
L Σ \u003d 10 lg (10) 0,1LL + 10 0,1L2 + ... + 10 0,1LN), dBA (4.6)
L Σ \u003d L 1 + ΣΔ L i (4.7)
For permanent noise, remote control in octave bands with medium meterometric values \u200b\u200bof frequencies is set: 31.5, 63, 125, 500, 1000, 2000, 4000, 8000 Hz. To estimate the noise level allowed to use the sound level (dBA).
When exposed to an employee during the working day (shift) of noise with different temporal (permanent, non-permanent noise) and spectral (tone noise), the characteristics are measured or calculated equivalent sound level. To obtain comparable data, the measured or calculated equivalent levels of pulse and tone noise sounds increase by 5 dBA, after which the result obtained can be compared with the removal of noise without making a lower amendment.
4.6.1 Calculation of equivalent noise level
The equivalent noise level is calculated by formulas 4.8 or 4.9.
L Cp \u003d 10 lg (10 0.1 L 1 + 10 0.1 L 2 +10 0.1 L 3 + ... + 10 0.1 L n) - 10 LG N, DBA (4.8)
where: L 1, L 2, L 3, ... L n - measured levels, dBA,
n - number of measurements.
L Cp \u003d L sum - 10 LG N (4.9)
The summation of the measured levels according to formula 7 is carried out in pairs as follows. By the difference between two levels L 1 and L 2 in table. 4.16 Determine the additive ΔL, which is added to a greater level L 1, as a result of which the level L 1, 2 \u003d L 1 + ΔL is obtained. The level L 1.2 is summed in the same way with the level L 3 and the level L 1,2,3 is obtained, etc. The final result l sum is round to an integer number of decibels.
Table 4.16.
With equal terms levels, i.e. When L 1 \u003d L 2 \u003d L 3 \u003d ... \u003d L n \u003d L, L sum can be determined by formula 4.10.
L sum \u003d L 1 + 10 LG n, (4.10)
Table 4.17. 10 lg n values \u200b\u200bdepending on n.
When evaluating the working conditions on the noise factor, the time of exposure to the factor is estimated and the equiary value is determined according to Table 4.18.
Equivalent sound pressure level is the level of sound pressure, averaged time (dimension - dBA)
Table 4.18. Adjusting the noise level depending on the time of exposure
| Time | In the clock | 0,5 | 15 minutes | 5 minutes | ||||||||
| in % | ||||||||||||
| Amendment in DB | about | -0,6 | -1,2 | -2 | -3 | -4,2 | -6 | -9 | -12 | -15 | -20 |
4.6.2 Measuring noise at workplaces
When performing measurements covered all characteristic and repeated day-to-day noise situations(it is important to identify everything significant changes in noisein the workplace, for example, 5 dB (dBA) and more).
Duration of measurements within each reference time interval:
§ for permanent noise no less 15 S.;
§ For non-permanent, including intermittent, noise, it must be equal to the duration of at least one repeating working cycle or multiple several working cycles;
§ for non-permanent noise, - 30 minutes(Three measurement cycles of 10 minutes);
§ for pulse noise - no less time of passage of 10 pulses (recommended 15 - 30 s).
Noiseomers use for measurement, Fig.4.7.
Table 4.19. Maximum permissible levels of sound pressure, sound and equivalent sound level at workplaces with a special assessment of working conditions
Production vibration
Vibration- oscillatory movements of elastic bodies, structures, structures near the equilibrium position. The impact of vibrations per person is classified:
According to the method of transferring vibration per person;
In the direction of vibration;
By time action.
According to the transmission method, the general and local vibration distinguish (Fig. 4.8).
 1
|  2
|
Figure 4.8. Direction of coordinate axes under action of general (1): a) standing position; b) the position of sitting and local vibration (2): when covered: a) end; b) spherical surfaces.
The total vibration on the source of its occurrence is divided into
movement speed - excavators, cranes, concrete pavers, outdoor production transport;
a) at the permanent job places of industrial premises;
b) in workplaces in warehouses, in the canteens, household, duty and other rooms, where there are no cars generating vibration;
c) in workplaces in the premises of plant management, design bureaus, laboratories, training points, health care and other premises for workers of mental labor.
Local vibration is transmitted through human hands. It can be attributed to the exposure to the legs of a sitting person and on the forearm in contact with vibrating surfaces.
In the direction of action, vibration is divided in accordance with the direction of the orthogonal coordinate system.
According to the time characteristic, it differs:
permanent vibrationfor which the controlled parameter during the action changes no more than 2 times (by 6 dB);
non-permanent vibrationFor which these parameters change more than 2 times during observation (by 6 dB).
Under the action of vibration, vibrationability (vibration), frequency range and vibration exposure time are estimated.
Frequency range of perceived vibrations from1 to 1000 Hz. The fluctuations with a frequency below 20 Hz are perceived by the body only as vibration, and with a frequency above 20 Hz - at the same time as vibration and noise.
The total vibration causes changes in cardiovascular and central nervous systems, the appearance of pain in individual organs. Local vibrations affect the central nervous system, increasing blood pressure, cause a narrowing of capillaries in the tips of the fingers, lead to loss of their sensitivity (vibration), fig. 4.9. The vibration disease from local vibration is manifested by the attacks of the peeling of the fingers, a sensitivity impairment, grinding of the brushes. Muscle endurance reduces physical exertion. During the progression of the disease, there is a sensitivity impaired in the form of "high gloves" (from the elbow), there is a swelling of hands, tukoidability in the joints of the brushes in the morning, etc.
Fig. 4.9. Signs of local vibration disease
Under the influence of vibration, visual perception deteriorates, especially at frequencies (25-40) and (60 - 90) Hz. Vertical vibration is particularly unfavorable for working in a sitting position, horizontal - for working standing. The effect of vibration per person becomes dangerous when the frequency of the workplace fluctuations is approaching the frequency of its own oscillations of the human body organs: (4-6) Hz - head oscillations relative to the body in the standing position, (20-30) Hz - in the sitting position; 4-8 Hz - abdominal cavity; 6-9 Hz most of the internal organs; 0.7 Hz - Kip, cause sea disease.
4.7.1. Vibration rationing
The normalized and controlled vibration parameters, according to CH 2.2.4 / 2.1.8.566-96, the average quadratic values \u200b\u200bof vibration resistance (A) or vibration accuracy (V) are used, as well as their logarithmic levels in decibels (dB).
The logarithm of the level of vibration accuracy (LV, DB) and vibration resorts (L A, DB) is determined by formulas:
, (1)
, (2)
where 5 × 10 -8 and 1 × 10 -6 are the reference values \u200b\u200bof vibration and acceleration.
The normalized frequency range is set:
For local vibration in octave bands with medium-beometric frequencies (F 2 / F 1 \u003d 2) - 8, 16, 31.5, 63, 125, 250, 500, 1000 Hz;
For general vibration in octave and 1/3 octave bands with medium meterometric frequencies (F 2 / F 1 \u003d V2) - 0.8, 1, 1.25, 1.6, 2.0, 2.5, 3.1, 4.0, 5.0, 6.0, 10.0, 12.5, 16.0, 20.25, 31.5,40, 50, 63, 80 Hz.
In tab. 4.20 - 4.24 shows permissible values \u200b\u200bfor vibrations of various categories with a working shift of 8 hours.
Table 4.20. Maximum allowable levels of local vibration
| Medium meterometric frequencies of octave stripes, Hz | Extremely permissible levels on axes x l, y l, z l | |||
| Vibrousness | vibration signs | |||
| m / s · 10 -2 | DB | m / s 2 | DB | |
| 1,4 | ||||
| 1,4 | 1,4 | |||
| 31,5 | 1,4 | 2,7 | ||
| 1,4 | 5,4 | |||
| 1,4 | 10,7 | |||
| 1,4 | 21,3 | |||
| 1,4 | 42,5 | |||
| 1,4 | 85,0 | |||
| Corrected, equivalent corrected level | 2,0 | 2,0 |
Table 4.21. Maximum allowable vibration values \u200b\u200bof jobs
| Hz | Maximum permissible values \u200b\u200bon axes x, y, z | |||||||||||||||
| For vibration | For vibrations | |||||||||||||||
| m / s 2 | DB | m / s · 10 2 | DB | |||||||||||||
| in 1/3. | in octave | in 1/3. | in octave | in 1/3. | Octave | in 1/3. | in octave | |||||||||
| Z. | X, W. | Z. | X, W. | Z. | X, W. | Z. | X, W. | Z. | X, W. | Z. | X, W. | Z. | X, W. | Z. | X, W. | |
| 0,8 | 0,70 | 0,22 | 4,50 | |||||||||||||
| 1,0 | 0,63 | 0,22 | 1,10 | 0,40 | 10,00 | 3,5 | 20,0 | 6,30 | ||||||||
| 1,25 | 0,56 | 0,22 | 7,10 | 2,80 | ||||||||||||
| 1,6 | 0,50 | 0,22 | 5,00 | 2,20 | ||||||||||||
| 2,0 | 0,45 | 0,22 | 0,79 | 0,45 | 3,50 | 1,78 | 7,10 | 3,50 | ||||||||
| 2,5 | 0,40 | 0,28 | 2,50 | 1,78 | ||||||||||||
| 3,15 | 0,35 | 0,35 | 1,79 | 1,78 | ||||||||||||
| 4,0 | 0,32 | 0,45 | 0,56 | 0,79 | 1,30 | 1,78 | 2,50 | 3,20 | ||||||||
| 5,0 | 0,32 | 0,56 | 1,00 | 1,78 | ||||||||||||
| 6,3 | 0,32 | 0,70 | 0,79 | 1,78 | ||||||||||||
| 8,0 | 0,32 | 0,89 | 0,63 | 1,60 | 0,63 | 1,78 | 1,30 | 3,20 | ||||||||
| 10,0 | 0,40 | 1,10 | 0,63 | 1,78 | ||||||||||||
| 12,5 | 0,50 | 1,40 |
Hygienic requirements for coal industry enterprises are established by the sanitary rules and the norms of SanPiN 2.2.3.570-96. The purpose of this document is to preserve the health of working through the restriction of adverse action of dust, physical, chemical and other harmful factors accompanying work at coal enterprises, prevention and reduction of the risk of development of occupational diseases (pneumoconiosis, dust bronchitis, vibration disease, hearing loss, diseases of the musculoskeletal system and the peripheral nervous system, intoxication, etc.), as well as industrially determined diseases by creating permissible working conditions, rational organization of labor and recreation, restrictions on the time of the effects of adverse factors when exceeding permissible levels and conducting special medical and preventive measures.
The basis for events to reduce the effects of harmful substances in the air of the working area is hygienic rationing. A feature of the normalization of air quality is the dependence of the effects of pollutants present in the air, on the health of workers not only on the value of their concentrations, but also on the time interval duration, during which a person breathes by these air. Therefore, in the Russian Federation, as well as around the world, 2 standards are installed for pollutants:
- - a standard designed for a short period of exposure to pollutants. This standard is called "maximum permissible maximum-time concentrations".
- - a standard, calculated for a longer exposure period (8 hours, day, for some ages). In the Russian Federation, this standard is set for 24 hours and is called "maximum permissible average daily concentrations".
The maximum permissible concentrations (MPC) of dust in the air of the working area are mounted by hygienic standards GN 2.2.5.1313-03 "Maximum permissible concentrations of harmful substances in the air of the working area".
Maximum permissible concentrations of coal dust:
- - Dust, content of more than 70% silicon dioxide - 1 mg / m 3
- - Dust, content from 10% to 70% silicon dioxide - 2 mg / m 3
- - Dust, content from 2% to 10% silicon dioxide - 4 mg / m 3
- - Dust, content of less than 2% silicon dioxide - 10 mg / m 3.
In Russia, the gravimetric concentration of all dust inhaled from the air of the working area is measured and normalized. In other developed countries (except CIS countries), primarily gravimetric concentration of dusty (thin) dust fraction is measured and normalized.
Reducing the level of impact on workers of harmful substances is achieved by conducting technical, technological, sanitary and hygienic measures.
Technological measures include such as the introduction of continuous technologies, automation of production processes, remote control, equipment sealing.
Sanitary activities are equipment of workplaces by local exhaust ventilation or local suction, equipment shelter with solid dustproof housings with efficient air aspiration and others.
In cases where technological and sanitary activities do not completely exclude the presence of harmful substances in the air environment, medical and preventive measures are carried out: the organization and conduct of mandatory medical examinations, respiratory gymnastics, inhalation, ensuring therapeutic and prophylactic nutrition or milk.
There are many sectoral documents describing the dust situation in the room. This is a slope, GOST and consider it from their own, professional points of view. But nowhere in them there are no numbers restricting the content of dust in household and office space. This is primarily due to the fact that in the decoration of these categories, a variety of materials are used. Namely from the finishing materials used, the materials used in the equipment and the design of the premises (ventilation and air conditioning). And by installing dust standards for household and office premises, designers risk not to meet them.
In 2004, the most wide document was put into effect by defining dust regulations in the air. It is "Interstate standard GOST ISO 14644 -1-2002, clean rooms and associated controlled environments, part 1, classification of air purity."
Here is a long and uncomplicated name. For us, in this case it is interesting to the table. 1. From section 3.
Previously, there was GOST R 50776-95, which is characterized by rationing the content of microorganisms (see Table 1, the column highlighted with pink color), and the values \u200b\u200bof the amount of dust are not rounded.
Given that we need landmarks on the concentration of dust, the data of these two guests "s are summarized in one table.
Table 1, classes of cleanliness on air suspended particles for clean rooms and clean zones
| Class N iso. (N - classification number) |
Maximum permissible concentration of particles, particles / m 3, with dimensions equal or large following values, microns | MK | |||||
| 0,1 | 0,2 | 0,3 | 0,5 | 1,0 | 5,0 | ||
| Class 1 Iso. | 10 | 2 | ND | ND | ND | ND | ND |
| Class 2 ISO | 100 | 24 | 10 | 4 | ND | ND | ND |
| Class 3 Iso | 1000 | 237 | 102 | 35 | 8 | ND | ND |
| Class 4 Iso. | 10000 | 2370 | 1020 | 352 | 83 | ND | ND |
| Class 5 Iso. | 100000 | 23700 | 10200 | 3520 | 832 | 29 | 5 |
| Class 6 Iso. | 1000000 | 237000 | 102000 | 35200 | 8320 | 293 | 50 |
| Class 7 Iso. | NK | NK | NK | 352000 | 83200 | 2930 | 100 |
| Class 8 Iso. | NK | NK | NK | 3520000 | 832000 | 29300 | 500 |
| Class 9 Iso. | NK | NK | NK | 35200000 | 8320000 | 293000 | NK |
| Due to the uncertainties arising from the score of particles, the classification should use concentration values \u200b\u200bthat have no more than three significant digits. | |||||||
nK - the countable concentration of particles of this size for this class is not controlled,
nD - particles of this and larger size in the air should not be
MK - extremely permissible number of microorganisms, pcs / m 3
I have not yet found data related to the purity of air in household and office space. Although I came across a standards for clean premises of medical institutions.
And knowing the tough rationing of dust content in the air of pure industrial premises with a category, we can conclude that classes (categories) 7, 8, 9 are closest to the office (7, 8) and household (9) premises.
Conclusion
Although GOST determines the category "for clean rooms and clean zones", we are interested in the ISO 9 class, as (in my opinion), the closest to household premises and the ISO 7 and 8 class for office space equipped with air conditioning and air filtration, respectively.
The above figures can only be used as guidelines when conducting evaluation calculations for electronic filters of electronic and computing equipment and its operational regulations.
For accurate calculations, the values \u200b\u200bof the dust levels indicated in the passports of the premises, where the equipment is located.
For your informationThe amount of dust in the atmospheric air can be quite different. In the area with a solid green array, over the lakes and rivers, the amount of dust in the air is less than 1 mg / m 3, in industrial cities - 3-10 mg / m 3, in cities with dysfunted streets - up to 20 mg / m 3. Particle dimensions range from 0.02 to 100 microns. Sanitary standards of the USSR- (CH 245-71) Limit the average daily maximum permissible concentration of non-toxic dust to it atmospheric air 0.15 mg / m 3However, in reality, the concentration of dust is often more, therefore it is better to proceed from experienced data on the degree of air pollution in a particular area. The concentration of suspended substances in the atmospheric air of Novosibirsk exceeds the maximum permissible concentrations. If MPK is 0.15 mg / m³, then in 2004 it was 0.26 mg / m³, in 2005 - 0.21 mg / m³, and in 2006 - 0.24 mg / m³. In the center of the capital of Estonia Tallinn, a concentration of fine dust was registered to 0.07 mg / m 3. In England, the air of cities in which residential quarters with fireplace heating are combined with large industrial enterprises, characterize divetenance up to 0.5 mg / m 3, In the US, the concentration of dust in the air reached 1.044 mg / m 3, In Germany, the greatest concentration of dust was noted in the cities of the roar - up to 0.7 mg / m 3. The main danger to the human body represents precisely particles of the size of the tenths of the micrometer to 10 and especially up to 5 microns. The dust structure of household premises and offices differs from atmospheric dust and dust of industrial premises and significantly depends on their finishes and equipment and furniture placed indoors. |
Prepared by A.Sorokin,