Hat Manufacturing

HAT MANUFACTURING. Of the numerous productions of various types of hats for the hygienist, only the branch of Hat Manufacturing (H. p.) concerning the finishing of felt hats is of interest. Rabbit and rabbit fur is used for the production of felt hats. Special processing of the fur for felt hats is required so that the smooth surface becomes rough (without which felting is impossible) — for this purpose the skins are lubricated with a special composition invented in France in the 17th century. For a long time this composition (a solution of mercury in nitric acid) was a secret of the craftsmen, which is why the procedure of processing the skin received the name 'secretage'. Nitrogen oxides play a role only in the initial phase of the production process. Nitric acid mercury figures in all phases of the production process; it is precisely this that makes the production of felt hats extremely harmful, poisoning the worker's organism. The disassembly of the skins, their sorting with the elimination of tails, heads and paws, and then the cutting off of prominent coarse hairs (peshik) are accompanied by a great dusting of the air, but are not connected with the danger of intoxication with mercury. The danger of mercury poisoning and the harmful effect of nitrogen oxide vapors begins with the moment of 'lubricating' the skins with the 'secret'. Nitric acid causes burns to the skin if the hands are not protected by rubber gloves; mercury can easily be absorbed through scratches or enter the stomach through food contaminated with hands. Drying of the secreted skins is carried out in special drying ovens at a high t° (not less than 60°). The unloading of the drying oven by workers is associated with the inhalation of nitrogen oxide vapors, the condensation of which, according to Heim, reaches 250 cm^s per 1 m³ of air, and the dust particles containing mercury released from the skins. Brushing the skins is accompanied by an especially abundant release of mercury dust (the combination of mercury with keratin of the hair) and dust of nitric acid mercury. According to the research of the American author Harris, the fur usually contains 0.939% of the first type of dust and 0.662% of the second type. In the air of premises in which the skins are brushed, up to 75 mg of mercury dust per 1 m³ was found. When trimming the fur, the worker also has to continuously inhale dust containing mercury. In the conditions of peasant production, all the above-described production processes are carried out in peasant huts, and Russian stoves, in which food is prepared, serve as drying ovens. The fur arriving from the shearing factories requires preliminary processing before undergoing felting. The process of cleaning the fur is called 'puchenie' and is carried out with the help of an instrument representing a bow with a stretched string. On the newest factories, 'puchenie' is produced on special machines representing a long box equipped with grids retaining the refuse and an endless belt on which the clean fur is laid. The process of puchenie is accompanied by a colossal dusting of the air. In machine pucheniya, up to 40 mg of mercury per 1 m³ of air was found. Stuffing of the caps in the manual method is carried out with the help of a vibrating string. In the machine method, the fur, moved by a fan, wraps around a metal cone. After stuffing the cap, it undergoes felting with heating on a tile and moistening with water spray. In the next process — 'washing' of the cap — the fabric of the latter shrinks, the felt becomes even denser, and the cap decreases in size. In the described processes (felting, washing, dyeing), the harmfulness is the high t° and high humidity. The question of professional mercury poisoning in H. p. arose in France earlier than in other countries, and here it acquired the greatest sharpness. This is explained by the fact that France (and partly Belgium) has long almost monopolized the most dangerous with respect to mercury poisoning branch of fur shearing of Hat Manufacturing. In the beginning of the 19th century, the doctor Breaud established the fact of continuous mercurialism among the workers of fur shearing factories. In 1869, Hilleret proved that mercury plays the role of an intermediary during secretage, and the main action belongs to nitrous acid, which is released in the dryer when heating the secreted skins and at the moment of its origin acts on the horny layer of the hair. In place of mercury, Hilleret proposed using molasses with nitric acid. In 1901, V. A. Levitsky (then a sanitary doctor of the Moscow provincial zemstvo) carried out a detailed study of the physical state, morbidity, mortality and birth rate of the population of Podolsky uyezd. An analysis of these materials revealed a district (Klenovsky and neighboring volosts) with extremely low indicators of physical state, with a high indicator of morbidity and with a deficient population growth. The examination carried out in 1902 revealed a picture of the degeneration of the population of this district on the basis of mass chronic mercury poisoning. The examination confirmed mercurial stomatitis in 96.26% of the examined, nervous system diseases on the basis of mercurialism in 71.69%, in 4 examined — characteristic for mercurialism mental disorders, arteriosclerosis at the age of 20-40 in 39.91%, etc. To seek ways for radical improvement of H. p., Levitsky was sent abroad. In France, the possibility of applying a mercury-free method of felt production (Jurdy-Lussigny) was established. The Moscow zemstvo organized a special artel, the work of which according to this method was to proceed under special control. For 4 years of its existence, this artel actually produced a wide experience of applying mercury-free felt and thereby gave the possibility to carry out a wide and impartial examination on the question of the practical feasibility of applying mercury-free secretage in H. p. In the old peasant district of the Moscow region after this, the application of the old mercury secretage was resumed. The question acquired renewed relevance only after the October Revolution, when the Moscow Labor Department organized the production of caustic potash in the hat district and invited as an instructor and propagandist of mercury-free methods an enthusiast of this matter, worker P. P. Kukovkin. To verify the value of other mercury-free methods and the detailed development of the Jordy-Lussigny method in 1930, an experimental laboratory was organized by the Institute for the Study of Occupational Diseases named after Obukh. In this laboratory, the Lussigny method (with caustic potash) was again recognized as the most valuable. However, the introduction of mercury-free secretage did not exceed 50%. Only from the time of the formation of the Felt Trust and the complete industrialization of hat manufacturing by the construction of three large felt factories, the question of the elimination of mercury in hat manufacturing in the USSR was finally resolved, and since 1932, all production has completely switched to the practice of mercury-free secretage.