C. Dampness Aside from high atmospheric humidities which have been dealt with under "Abnormalities of temperature" there remains to be considered exposure to constant wetting. Tankmen, vatmen, and washers, for example, may be required to carry on their duties constantly in wet clothes. Such exposures are brought together under the heading "Dampness." Rheumatic and neuralgic affections may result from exposure to dampness, which also may be a contributing factor to respiratory infections. When dampness is a feature of any industrial process, work places should be supplied with drain channels to prevent the accumulation of water, or use should be made of duck boarding. Adequate waterproof clothes, such as rubber boots, rubberized aprons, and so forth, should be supplied. SYMPTOM, CONDITION, OR DISEASE TO LOOK FOR Respiratory, neuralgic, and rheumatic affections. Beamhouse workers tan- Flush tenders (alumi- Pulp-mill employees pulp) Boiler washers Brewers Brickmakers Cable splicers Caisson workers Canners Cartridge-cup washers Cartridge felt and wad makers Cartridge shot shell paraf- Cellulose makers Clay and bisque makers Clay-plug makers tery) Cloth preparers Glass cutters Glass finishers Glaze dippers (pottery) Guncotton washers Rayon makers Refrigerating-plant work ers Sagger makers Screen tenders (pulp mill) Shavers (felt hats; fur; Slaughterhouse workers Hydraulic construction | Soap makers workers Hydraulic miners Ice-cream makers Lasters (shoes) Concentrating-mill work-Match-factory workers D. Defective Illumination Defective illumination, characterized by insufficient quantity of light, glare (light out of place), unsuitability of color, and improper diffusion and distribution of light, is the cause of eye fatigue, headache, dizziness, and errors of refraction. Miners' nystagmus, a condition in which the eyeball acquires a peculiar involuntary oscillatory movement, is attributed to the effects of insufficient illumination. This disease is very common among British miners, but apparently is not found to any extent among American miners. The explanation for the favorable situation of the American miner probably lies in the better illumination of the American mines. Not only is defective illumination the cause of these serious impairments of vision but it is an important factor in reduced working efficiency in industry generally, and it is a very frequent cause of industrial accidents. The hazard of defective illumination is not limited to any single industry or group of industries. It may be present in any plant. Men engaged in occupations requiring close, fine work, such as jewelers, engravers, clerks, and mail sorters, are especially likely to suffer from exposure to this hazard. It is a comparatively simple matter to provide for all the requirements for properly illuminating workplaces in some industries, while in others the advice of illuminating engineers is required. The American Standard Code of Lighting for Factories, Mills, and Other Work Places, prepared by the Illuminating Engineering Society, New York City, is an excellent reference work for those who have need of technical knowledge on this subject. SYMPTOM, CONDITION, OR DISEASE TO LOOK FOR Nystagmus, eyestrain, deficient vision due to astigmatism or hyperopia, headache, giddiness. Eyestrain contributes to neurasthenia. OCCUPATIONS WHICH OFFER SUCH EXPOSURE Virtually all occupations. The following and similar occupations are especially subject to this hazard: Dust arising from industrial processes is produced by mechanical action, such as grinding, crushing, cutting, drilling, and so forth. Its composition is similar to the substance or substances from which it is derived, and in this respect it differs from fume, which is the result of chemical action and which does differ from the substance of its origin. The size of dust particles is important because this influences their ability to be inhaled into the finer air passages and reach the pulmonary parenchyma. Poisonous dusts are not considered in this section but under their appropriate headings relating to their composition. For practical purposes industrial dusts are divided into two classes, organic and inorganic. ORGANIC DUST Organic dusts contain carbon and are largely derived from substances of animal and plant origin. Examples of these are textile dusts, flour, sugar, wood, leather, and feathers. Organic dusts may irritate the skin, causing an occupational dermatitis or may irritate the conjunctiva. Many, if not most, organic dusts may cause an allergic reaction in some persons. When present in very large quantity, any organic dust may cause irritation of the upper air passages. Some woods may also cause skin irritation, notably Brazil wood, satinwood, teak, some mahoganies, cocobolo, California redwood. Organic dusts do not cause pneumoconiosis or pulmonary fibrosis of a specific disabling nature. The particles of many types of organic dusts are not of the size or shape to permit them to penetrate to the lung tissue and those which do gain entrance into the body are absorbed. Coal is an organic dust, but on account of its origin is sometimes classed with the mineral dusts. Coal dust does get into the lungs, causes pigmentation, and may stimulate the production of fibrous tissue but will not produce a disabling pneumoconiosis. The "miners' asthma" of anthracite miners has been shown to be in fact a silicosis, modified by the presence of coal dust along with the silica, and is properly termed anthraco-silicosis. INORGANIC DUST Inorganic industrial dusts are mostly metallic and mineral. Of all the various types of such dusts, only those containing "free" or uncom bined silica will produce the specific pneumoconiosis known as silicosis. Other inorganic dusts may cause some pulmonary fibrosis of a benign or nondisabling character. The action of silica dust upon the lungs is probably chemical, and the dust particles producing the reaction are mostly those from one-half to three microns in diameter. The reaction of silica is the production of nodules, distributed throughout both lungs, producing a characteristic appearance on the X-ray film. Another effect of silica is to stimulate tubercle infection and severe cases of silicosis frequently die with tuberculosis. Dusts containing silica in combined form do not cause silicosis. However, one such dust, asbestos, a magnesium silicate, will produce a characteristic fibrosis. This is quite different in its pathology from silicosis, and has a characteristic "ground glass" appearance on X-ray film. Ánimal experimentation indicates that the action of asbestos is probably mechanical, since it cannot be produced in other than the pulmonary tissue. Asbestosis may cause disability, and a few fatal cases have been recorded, but in those cases showing marked disability, other organic disease is usually also present. The control and prevention of silicosis and asbestosis depends on both medical and engineering supervision. Periodic X-ray examination of workmen exposed to these dusts is essential. Engineering methods for the control of dust comprise: (1) The use of exhaust systems or suction devices which entrap the dust at its point of origin. (2) The use of water, and occasionally oil, to lay the dust and keep it out of the atmosphere. Both these methods may be combined. (3) The use of enclosed systems for dust-causing procedures, properly exhausted. (4) Increased ventilation, thus diluting the amount of dust in the air and decreasing its concentration. (5) The use of helmets or respirators, of a type approved by the United States Bureau of Mines, where intermittent exposures, not otherwise controllable, are involved. 1. Organic Dust SYMPTOM, CONDITION, OR DISEASE TO LOOK FOR Irritation of the skin and upper air passages, allergic effects, asthma. 2. Inorganic Dust Containing Free Silica SYMPTOM, CONDITION, OR DISEASE TO LOOK FOR Cough, dyspnea, pleuritic pains, deficient chest expansion, dullness, diminished resonance, colds, pleurisy, tuberculosis, hemoptysis. OCCUPATIONS WHICH OFFER SUCH EXPOSURE Bisque-kiln workers Blasters-underground (siliceous rock) Brickmakers tories) (refrac (sand Burrers-needles Chippers (foundry) Sandpaper makers Sandstone quarriers, crushers, dressers Sawyers (siliceous stone) (sand- Scouring powder makers Scrapers (foundry) Silicon alloys makers Slate grinders Smelter workers stone wheels) Miners in siliceous rock Clay and bisque makers Planer men (siliceous rock) Coremakers ore Crushermen (siliceous rock) Quarrymen (siliceous Cutlery grinders (sand- Rubber workers (filling) stone wheels) Drillers (siliceous rock) Enamelers (free silica frits) Ferrosilicon makers Sandblasters Sand cutters Sanders (quartz paper) 3. Inorganic Dust (except Asbestos) Containing no Free Silica SYMPTOM, CONDITION, OR DISEASE TO LOOK FOR Exposure to inorganic dusts containing no free silica has been found in some instances to be associated with simple linear fibrosis (nonspecific benign fibrosisGardner) not associated with disability. The exact relationship of various dusts to this type of fibrotic reaction is not entirely clear. OCCUPATIONS WHICH OFFER SUCH EXPOSURE |