Hot Shops

HOT SHOPS, workshops where a worker's organism is exposed to the action of high temperatures. The following main hazards are distinguished in them: 1) high ambient air temperature, 2) direct action of radiation emanating from incandescent bodies, 3) the danger of direct contact with these bodies or their particles (sparks and splashes). All these factors are encountered in hot shops either separately or in various combinations. I. The main harmful effect on the worker's organism of high ambient temperature, and partly the effect of thermal radiation, is the disruption of the body's thermal equilibrium, as a result of which there may be either heat stroke or other occupational diseases, such as: 1. Decreased resistance of the organism and, as a consequence, frequent colds when moving to conditions of lower temperatures. 2. Diseases of the cardiovascular system (especially in the form of sclerosis) as a result of its increased load. 3. Metabolic disorders (a worker loses up to 4-5 liters of sweat and up to 25 grams of chlorides per day—an amount exceeding that which usually enters with food during the day. Increased water drinking leads to the further leaching of chlorides from the body). 4. Tendency to gastrointestinal diseases (due to the action of both high temperature and large amounts of drinking water—often unboiled and cold). 5. Decreased appetite. 6. Decline in nutrition and weight loss. 7. Anemia. 8. Functional nervous disorders. Under conditions of high temperature, a large number of professions work in various branches of industry: metallurgical and metalworking (usually in combination with radiation and the action of sparks and splashes of molten substances), chemical (especially in the production of glass and porcelain), mining, sugar, oil refining, textile, paper, etc. In underground mining operations in some mines, in drying rooms, laundries, baths, in a number of workshops of sugar-refining production, in wet spinning frames in textile production, etc. The air temperatures of the working room in hot shops vary from those slightly exceeding the norm to very high ones (thus, during selection from kilns in porcelain and earthenware production, up to 175° was noted). Depending on the temperature, the time of continuous stay in a given room also ranges from 10-15 minutes to a whole working day. In a large number of cases, this time exceeds what is permissible by hygienic considerations. Measures to protect workers from the overheating of the organism. 1. In all cases when high temperature in the room is not required by production conditions—its reduction: by insulating heat-radiating surfaces, rational ventilation, increasing the cubic capacity of the room, etc. 2. Reduction, where possible under production conditions, of air humidity (up to 20-30% relative humidity). 3. Combating dust in work rooms (by mechanizing production processes, introducing rational equipment, proper ventilation, etc.). 4. Maintaining the worker's body in cleanliness (work clothing that protects against dust and is washed frequently enough, installation of warm showers, issuance of soap). 5. Establishment of periodic rest breaks during which the worker can rest in a specially adapted, cooler room (periods of work and breaks depending on the degree of hazard). 6. Use of water with a 1% solution of table salt for drinking (which helps restore the disturbed salt balance). 7. Work clothing made of smooth cotton fabric (properties: softness, flexibility, immutability of these properties when wet, good ability to absorb and release moisture, good washability, good air permeability). In case of danger of contact with flame, sparks, and splashes of molten minerals and metals, cotton fabrics are dangerous in terms of ignition and must be replaced by less hygienic, but safer linen fabrics. 8. Depending on the degree of hazard—reduction of the working day and granting workers additional leave. 9. Where possible, reduction of physical work of workers by mechanizing the corresponding processes. II. The degree of action of radiant energy depends on the temperature of the radiation source. When heated below certain temperatures (for iron around 500°), practically only thermal rays are separated [examples: furnace mirrors, the surface of cooking boilers and apparatus, cooling (dark) billets, metal objects, etc.]. As the temperature rises, the radiation source begins to emit, in addition to thermal rays, visible rays to a noticeable extent, starting from red and successively covering the entire light spectrum (iron at 1,300°). This includes radiation from heat treatment furnaces, furnaces for heating billets, radiation of white-hot solids (e.g. in rolling departments, smithies), molten metals during pouring, etc. Open-hearth and other melting furnaces (t° 1,300-1,800° and higher) give the full thermal and light spectrum. At electric welding temperatures (3,800-4,000°), ultraviolet rays also have a noticeable effect. All these types of rays act not only on the surface of the body, but are also absorbed by some of its tissues, causing pathological changes in them. The intensity of the action of thermal rays depends on the temperature of the source, its size, the distance from the worker, the duration of exposure, the size of the radiating opening (if it is a furnace), the ability of the irradiated body to absorb thermal rays, and the cooling action of the environment (ambient air temperature, its movement, etc.). Thus, the heating of the worker's body in the premises of open-hearth, rolling, blast-furnace, and other shops can be very uneven, especially in the cold season and in poorly protected workshops (e.g., 100-150° was noted in front of the worker's chest and 20-30° behind his back); having stepped back a few steps to the side of the furnace, he can immediately fall into temperatures down to 0° and below. Temperatures at the workplace can reach very high degrees (on the loading platform of the open-hearth furnace in front of the open damper up to 250-300°). A worker's presence in such conditions can be measured by only a few seconds, after which he either jumps aside or is (periodically) replaced by a comrade. Sharp changes in the heating and cooling of the organism (especially in the cold season) place an increased load on the cardiovascular system and often cause both painful changes in it and general colds.—The influence of the flow of thermal radiant energy on the skin causes burns of all three degrees, erythema-like rashes, chronic inflammation, thickening, and pigmentation (according to White, "stokers' knees", "bakers' hands"; according to many observations, "noses and chests of workers in front of melting furnaces"). The influence of thermal rays on the eyes, according to most authors, can manifest itself, for example, in the so-called "glassblowers' cataract". Light rays act predominantly on the eyes of workers, causing damage to the retina and choroid at high intensity. During electric welding, along with light rays, ultraviolet rays also act (in direct and reflected form); the question of the nature of the action of the latter is not yet entirely clear; according to the prevailing opinion, they are absorbed predominantly by the conjunctiva, cornea, and iris, causing their disease. On the skin, ultraviolet rays can cause erythema and burns followed by pigmentation. Measures to protect workers from the effects of radiant energy. 1. All measures indicated above regarding the danger of the organism overheating. 2. Special protective devices; work clothing must be provided in areas of greatest thermal radiation with local pads of loose, porous, rigid, and light woolen fabric (of the "Caucasian cloth" type); footwear and hats that well protect against heat (best of all dense felt or coarse wool hats); hats with folding brims; mittens with padding for protection against heat; glasses with lenses that do not transmit harmful rays (strict standardization in accordance with the radiation source) and provide the best contrast when viewing the necessary objects of work. At high power of thermal radiation, glasses, to avoid heating the frame, must be attached to the hat. During electric welding, both the face and eyes must be protected; the latter in such a way that reflected ultraviolet rays cannot enter them (a leather light shield-half-helmet closing well but giving access to air, with a frame for colored glass). 3. Arrangement of air-blast, water, safety curtains between the open opening of the furnace and the worker standing in front of it; protection of workers, wherever possible, with shields that do not let heat through; insulation or artificial cooling of heated surfaces where permissible by production conditions; mechanization of production, reducing or eliminating the presence of workers in the area of strong radiation, etc. III. Direct contact with highly heated bodies occurs predominantly in the metallurgical and metal industry (most often in combination with radiation and high room temperature), chemical, mining, sugar, food, glass, porcelain-ceramic, and a number of other industries.

Active factors: a) danger of contact with flame (when working at crucible furnaces, changing covers of Martin furnaces, charging shaft furnaces, when working at flame furnaces, boiler rooms, heating furnaces, etc.); b) flying particles of red-hot metal or its oxides (scale) - during work in rolling mills, smithies, foundries during shaped casting, etc.; c) splashes of molten metals, slags and other substances - during work in foundry and melting shops of the metallurgical industry, during melting and calcining of various substances in the chemical and mining industries, etc.; d) contact with insufficiently cooled solid items (for example: during the removal of finished castings and other products of hot processing, during many operations in glass, porcelain-ceramic, brick and other productions). All these factors can cause burns of all three degrees. If sparks and splashes get on clothing, accidents are possible if the latter flares up. Accidents also include the getting of large quantities of molten and red-hot substances onto a worker. Protection measures for workers: rationalization of production aimed at reducing the flying of splashes and the possibility of splashing of molten substances, for example: mechanization of pouring, moving and pouring of these substances, preventing moisture in melting, ladles, molds; absence of clutter and crowding in the foundry yard; appropriate lighting of foundries; rationalization of labor processes of both individual workers and their collective, etc. - Individual protection of workers: glasses with splinter-proof lenses that do not narrow the field of vision, in a ventilated and slightly heating frame; special clothing made of non-flammable or flame-retardant material (wool is best, then less hygienic and worse-protecting linen fabrics; cotton is contraindicated). Cut that does not allow sparks to get stuck. With very strongly expressed sparks and splashes, as well as with strongly expressed other above-mentioned thermal factors - local asbestos special clothing for permanent protection (aprons, mittens, gaiters) or full (robes) - for temporary. In productions where splashes cannot cause ignition of clothing (sugar production, a number of chemical industries, food and flavor production, etc.), cotton fabrics are recommended for special clothing as more hygienic and well-washing. Protection of workers is also achieved by rationalization of production and work processes. - In addition to the purely thermal factors considered here, in hot shops a number of hazards are observed, varying depending on the nature of production (dust, gases, noise, body concussion, harmful chemical reagents, etc.). In the legislation of the USSR relating to the reduction of the working day and the granting of additional leave in hot shops, these points are taken into account along with the action of high temperature. Extracts from the current labor legislation of the USSR and union republics. 1) Professions of hot shops for which a reduced (6-hour) working day is established. Mining industry. All underground workers whose work is associated with a constant stay during work at temperatures above 28°. Metalworking industry. Workers in the smelting of copper sulfide ores at foundry and shaft furnaces. Workers in black copper smelting in shaft furnaces and in copper bessemerization. Workers in the smelting of zinc and lead from sulfide ores. Workers in the roasting of mattes and sulfide compounds in general in heaps. Puddlers and hook men. Casters and copper smelters with continuous work. Oxyfuel welders and cutters with continuous work with acetylene and voltaic arcs. Work associated with the extraction of mercury, arsenic and white phosphorus (hot works here are ore roasting and substance sublimation). Hot-dip tinners with continuous work. Chemical industry. Workers at furnaces for obtaining chromium mass. Municipal services: workers of the retort department at gas plants. Soda production - lime unloaders from the circle in the pot department, working at an ambient air temperature of 35°. Glass production - glassblowers and their assistants on continuously operating furnaces. Aniline-dye industry - workers engaged in the distillation of hydrocarbons on coke ovens. Production of red lead and litharge - workers at furnaces. Production of copper resinate - shift stokers (day stokers 4 hours). Pulp production - acid workers and assistants. Railway and water transport: ship stokers on solid fuel underway; slag cleaners of locomotive firebox ashpans with coal heating (continuous work throughout the working day); locksmiths and boilermakers on current repairs in the front fireboxes of hot locomotives with continuous work throughout the working day; bearing fillers (continuous and constant work throughout the working day). Sugar industry - bone charcoal burners. 2) Professions of hot shops for which additional leaves are established. Mining industry: petroleum production - tank cleaners and still cleaners. Acid plants: workers at furnaces. Metalworking industry. Blast furnace shop - all workers on the top, furnacemen, runners, slagmen, pig iron workers, gas workers. Open-hearth shop - gas workers, blast workers, ash workers on gas generators, steelmakers and assistants, chargers during manual charging, ladle workers, runners, masons for general furnace repairs, masons during hot repairs, machinists on charging machines and casting cars, subjected to the strong action of radiant heat. Rolling mills - welders and their assistants, rollers, hook men, wheelmen on universal mills, pressmen at puddling and welding furnaces, machinists at roller tables - subject to constant work near red-hot metal, workers on sheet-punching hammers (production of roofing iron). Tube-rolling mills - welders, assistants, straighteners of hot pipes. Tube-drawing mills - rollers and drawers (hot drawing). Copper-smelting shop - the same workers who have a reduced working day. Workers of the iron and steel foundry shop if casting is carried out at least 3 times a week; workers of the copper foundry shop - the same. Boiler department - stokers working on Moscow region coal, on solid mineral fuel (and peat), with manual loading, pokers and ashmen under the same conditions. Various industries - workers on welding and oxyfuel work, welding with fire, braziers, tinners, coppersmiths, gilders, hot galvanizers, blacksmiths and strikers for manual forgings on main work and with poor ventilation in the room; workers at roasting furnaces with constant work at temperatures above 30°; quenchers when heated in lead baths. Chemical industry. Hot shops of arsenic production - workers at sulfate furnaces, at chromium furnaces, at chromium salt dryers (without vacuum); at furnaces of nitric acid production, at pyrite furnaces; furnaces in the production of sodium sulfide, at furnaces and loading in the production of liquid glass. Rubber production - workers in the boiling of factice, varnish, oil, fat; working at hot presses at temperatures of 30° and above 25° with constantly high humidity; workers in the drying of oilcloth. Glass production - workers on the platform in the hut, shuralis. Match production - steamers with constant work. Bone-processing soap-making production - workers at silicate furnaces, workers of cooking departments, at fat-melting boilers, at the evaporator. Paint and varnish production - workers at lead red lead furnaces, lead smelters, resin smelters, varnish cookers, bottlers, paint cookers. Coal, elemental and soot production - stoker-roasters (when working on gas coal). Textile industry - workers of the dyeing department, on padding machines (with sulfur dyeing with black aniline) aging room, steaming, boiling department, paint cookers, workers of fulling production. Food and flavor industry - boiling of drying oil (using red lead and lead litharge), roasters and pressmen on constant work. Construction business - roasters for roasting in rotary kilns, loaders of shaft furnaces, Deutschschneider and Hofmann-Berlin. Municipal workers - workers of retort departments at gas plants, laundry washwomen. Pulp production - acid workers and their assistants; blacksmiths and strikers at tourms; stokers of crematories. Catering - cooks of restaurants, cafes, tea houses, canteens, taverns, shashlik houses and beer halls.

D. Shafranova.