ELEKTROSTANTsII, occupational health

From Big Medical Encyclopedia

POWER PLANTS — the industrial enterprises developing electrical energy.

On modern E. high extent of automation and mechanization of productions is reached. Distinguish two main types of power plants: hydroelectric power stations (hydroelectric power station) and thermal power plants (TPP). Depending on an energy source of thermal power plant are subdivided on steam-turbine, gas turbine and atomic. There are thermal power plants developing only electrical energy (state district power plant), and the stations giving heat (combined heat and power plant).

Producing departments of thermal power plant are fuel and transport, kotelnoturbinny, the workshop of chemical water purification. Technological process of the thermal power plant burning coal or peat the most difficult also includes such operations as reception, grind and transportation of coal by means of traveling bands to bunkers of crude coal (a path of fuel feeding); grind and drying of coal in mills of a grinding, supply of coal dust through a separator and the dust bunker on dust flues to torches of a copper (system of a pyleprigotovleniye). On the thermal power plants using fuel oil or gas, supply of fuel in a copper except for discharge of fuel oil, it is automated. Heat which is formed at fuel combustion in coppers is spent for heating of the water circulating in steel pipes and transformation of water into steam, to-ry under the big pressure up to 140 at (apprx. 14 MPas) on steam lines comes to the turbine and rotates a shaft of a turbogenerator. In the workshop of chemical water purification water treatment from mechanical impurities and solen by means of coagulants and special filters is carried out.

Management tekhnol. processes operators with central and block instrument assemblies, from the instrument assembly of a machine house on hydroelectric power station and local instrument assemblies on thermal power plant carry out generally. A considerable part of operations on a regulirov a niya tekhnol. process on hydroelectric power station it is automated.

The major adverse production factors on thermal power plant are the noise heating a microclimate, temperature drops; on certain sites of fuel and transport and boiler and turbine workshops the increased concentration of coal dust, carbon monoxide, carbon dioxide gas, a trioksikrezilfosfat take place, and at accidents — sulfur dioxide gas, hydrogen sulfide, ammonia, mercury, nitric oxides, vanadium.

On hydroelectric power station the high level of noise and vibration in a machine house is noted. Sources of intensive noise (see) on thermal power plant, level to-rogo 95 — 117 dB can reach (a scale And), electric motors of drive stations, various pumps and heaters, turbines, generators, mills of a grinding of coal, units of a zoloshlakoudaleniye, smoke exhausters, dutyevy fans are.

An adverse microclimate (see) it is generally characteristic of the boiler and turbine workshop where coppers, turbines, pumps, heaters, steam lines, boiler rooms of installation, and also the heated surfaces of the equipment, overlappings, extensive on the area, fittings are sources of calorification. The caloradiance from the equipment of turbine department makes 210 — 700 W/sq.m, from a copper and the boiler equipment — from 700 to 3140 W/sq.m. The microclimate of the fuel and transport workshop is defined by seasonal fluctuations of meteoconditions, and temperature drops of air of a working zone during the cold period of year can reach 20 °; in the workshop of chemical water purification the microclimate, as a rule, conforms to hygienic requirements.

Concentration of coal dust (see) in air of a working zone of the fuel and transport workshop and boiler department of the boiler and turbine workshop can exceed tolerance levels, especially at repair, cleaning of coppers and dust flues.

Insufficiently effective aeration, failure of fumes disposal groups, possible throwing of gases during the opening of glory-holes of torches and a letok of a copper, thermodestruction of oils, smazyvayushche-cooling liquids, in the workshop of chemical water purification — failure of the equipment, lack of forced ventilation can be the reasons of the increased concentration of a number of toxicants in air of a working zone of the kotelnoturbinny workshop.

Work of operators on E. it is characterized by the high neuroemotional pressure caused by responsibility, high information loading. Work of assistants to drivers, loaders of the car dumper, mechanics of a path of fuel feeding is followed by a considerable exercise stress. Regulation of work of a copper, turbogenerator, the service equipment is connected with need of frequent and quite often bystry movements. And intense operations of start-up and a stop of the equipment are especially heavy. Work on E. it is carried out round the clock, in shifts, that significantly aggravates tension of work. Existence of a large number of electric chains and need of repair work with them at non-compliance with safety regulationss increase danger of an electric trauma (see).

At operators and other persons working in unfavorable conditions of the production environment, perhaps early decrease in professional working capacity and reduction of duration of the labor period. At them a vegeto-vascular allotopia (see Dystonia vascular), an idiopathic hypertensia (see), the astenovegetativny syndrome, a myocardial dystrophy (see), chronic bronchitis (see), chronic gastritis (see), a peptic ulcer of a stomach and duodenum can develop (see. A peptic ulcer), neuritis of an acoustical nerve (see the Eighth cranial nerve), lumbosacral radiculitis (see). A certain quantitative dependence of pathology on a complex of adverse production factors is established.

On the nuclear power plants (NPP) a source of heat is the nuclear reactor (see nuclear reactors), in Krom allocation of energy of radioactive decay results from the managed chain reaction of division of heavy-nuclei (uranium, thorium or plutonium depending on the used nuclear fuel). As the heat carrier on most the operating NPPs water is used; in nuclear reactors on bystry neutrons use zhidkometallichesky heat carriers (e.g., liquid sodium); and in the gas-cooled nuclear reactors — gases (carbon dioxide gas, inert gases). The heated heat carrier comes to the steam generator, and the generated steam goes to the turbine.

5 MW first-ever NPP (el.) it is put into operation in the USSR in Obninsk on June 27, 1954. In the conditions of normal operation of the NPP are one of the most successful producers of electrical energy in the sanitary and hygienic and ecological relation. In the course of work of the NPP gas-aerosol, liquid and solid radioactive waste is formed, to-rye is exposed to processing, neutralization and special burial (see. Radioactive waste), and also waste heat (in the form of the heated water used for cooling of condensers of turbines of power plant). To the major adverse factors atomic E., arising at emergencies, belong gamma radiation (see), neutron fluxes and beta particles (see the Beta radiation, Neutron emission), the radioactive aerosols and gases, radioisotopes contaminating the equipment.

An integral part of system of radiation safety of personnel of the NPP and the population living on border of the sanitary protection zone (see) and beyond its limits, the radiation control exercised everywhere (see) which includes measurements of an individual dose of external radiation, power of an equivalent dose of gamma neutron emission, and also flux density of neutrons and beta particles is; concentration and nuclide composition of radioactive gases and aerosols in air of production rooms; level of pollution by radioactive materials of working surfaces, building constructions and equipment; skin and clothes of personnel; radioactivity and nuclide structure of gas-aerosol emissions and liquid dumpings into environment; contents of radioactive materials in various objects of the environment. The special services equipped with the modern dosimetric and spectrometer equipment control behind dosage rate and an annual dose of gamma radiation on the area in a radius up to 30 — 50 km from the NPP.

The long-term operating experience of the NPP in the USSR shows that the total annual dose of gamma irradiation of personnel of the NPP does not exceed a marginal exposure dose (traffic regulations) for the I group of critical bodies (all body, gonads, red marrow) — 5 rem a year. The NPPs unlike thermal power plant do not release into the atmosphere of ashes, sulfur dioxide gases and other harmful substances, do not consume oxygen of air.

Preventive actions for providing healthy working conditions and rational use of a manpower on E. shall include measures for optimization of noise level and vibration, parameters of a microclimate, lighting, for finishing content of dust and gases to maximum allowable concentration. Rationalization of intra replaceable and replaceable duties and rest is important. Predu to a prezhdeniye of incidence is promoted by preliminary and periodic medical examinations taking into account specifics of production factors (see. Medical examination). Preliminary psychophysiological selection of operators (see. Professional selection) is an important measure of ensuring high performance of work and preservation of health working.

Bibliography: Vorobyov E. I., etc. Radiation safety of the NPP in the USSR. Atomn. energy, t. 54, century 4, page 277, 1983; Kundiyev Yu. I., Navakatikyan A. O. and V. A. Gigiyen's Bay salts I am physiology of work on thermal power plants, M., 1982, bibliogr.; Kundiyev Yu. I., etc. The main results of researches in the field of hygiene and physiology of work at the power enterprises, Vestn. USSR Academy of Medical Sciences, No. 8, page 18, 1978; Standards of radiation safety of NRB-76 and ground health regulations of work with radioactive materials and other sources of ionizing radiation of OSP-72/80, M., 1981; Paltsev Yu. P. Questions of fight against dust on thermal power plants, the Gigabyte. work and the prof. having got sick., No. 10, page 15, 1970; Radiation safety in nuclear power, under the editorship of A. I. Burnazyan, M., 1981; Health regulations of design and operation of nuclear power plants: SP-AES-79, M., 1981; Nuclear power, the person and the environment, under the editorship of. And. P. Alexandrova, M., 1984.

Yu. I. Kundiyev, A. O. Navakatikyan, V. A. Buzunov, L. A. Ilyin.