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and the carbonate much more commonly than the sulphate. Chrome yellow is used for tinting in house painting and in coach painting; chrome green for painting window shutters; red lead in painting structural ironwork; and orange mineral for painting wagons.
Of these constituents lead carbonate is considered the most poisonous; but when sandpapering, mixing, or chipping off old paint, the red lead is the most dangerous, because it is lighter and floats in the air more easily. Chrome yellow is considered to be about as harmful as the red lead. Lead sulphate is not as dangerous as the lead carbonate, red lead, or the chrome yellow. It has been determined by scientific experiment that in human gastric juice the lead carbonate is a little more than twice as soluble as the sulphate; that the lead carbonate is distinctly more toxic than the sulphate; that both produce acute lead poisoning.
Experiments conducted to determine the effect which milk, when combined with the gastric juice, has upon the amount of lead dissolved brought the conclusion that when the milk and gastric juice are in equal proportion the hydrochloric acid of the gastric juice is so completely fixed by the milk proteins, or neutralized by the carbonates in the milk, that the mixture has virtually no solvent action on the lead salts.
On the basis of scientific investigations three practical suggestions have been made for safeguarding painters against poisoning: (1) That since lead carbonate is so much more toxic than the lead sulphate, lead workers as well as the State shall aim at the elimination of the use of the carbonate in all the industries where this is possible; (2) that since basic lead sulphate, or sublimed lead is poisonous, none of the precautions usually advocated for the protection of workers in lead be neglected by those handling lead sulphate; (3) that, in addition to taking other important prophylactic measures, workers in lead salts should drink a glass of milk between meals (say at 10 a. m. and 4 p. m.) in order to diminish the chances that the lead they have swallowed be dissolved by free hydrochloric acid of the gastric juice, as in some persons there is considerable secretion of gastric juice in the empty stomach.
Dust from the sandpapering of lead-painted surfaces is one of the most important causes of lead poisoning. The dust thus raised is inhaled and lodges on the nasal and pharyngeal mucous membrane and is then swallowed. Investigation has shown that the great bulk of this dust finds its way into the stomach and not to the lungs. This causes the poisoning of the workman, as the lead in the dust is dissolved by the free hydrochloric acid in the gastric juice and is easily absorbed. This dust is dangerous not only to the man doing the sandpapering, but also to the others working near. The danger can be entirely eliminated by the use of pumice stone and water in rubbing down coats, or, if it is a first coat where this is apt to raise the grain or on metal where it may cause rust, by moistening the sandpaper with some cheap mineral oil. Sandpaper so oiled lasts as well as when used dry, and the results so far as the work is concerned are as good when oiled paper is used as in dry sandpapering.
When metal surfaces are to be repainted they are usually chipped clean, and often the work is done by a machine using compressed air. This work is very dangerous, and a much better way, whether on wood or metal, is to burn the paint, causing it to curl and shrivel up, after which it can be easily scraped off. Some authorities speak of lead poisoning being acquired by the use of the burning method; but this is not apt to happen unless the painter should hold the flame long in one place and thus cause considerable smoke which might carry mechanically small particles of lead. The boiling point of lead is so high that the danger from evaporation from the heating required is very slight. Danger of poisoning from this method arises, however, when the burned paint is allowed to lie upon the floor of the shop until ground to dust. This dust is stirred up by the feet of the workmen or by moving materials, and is constantly inhaled and swallowed by the workmen. The scraps of paint should in every instance he cleaned up before they become dry.
The painter should be extremely careful in handling his food or tobacco and should avoid wearing dusty and paint-soaked clothing.
The dangerous vehicles are turpentine, benzine, naphtha, benzol, wood alcohol, and amyl acetate. Turpentine used as a dryer and for thinning is a constituent of many paints and varnishes. It sometimes makes up the entire vehicle. The inhaling of much turpentine-laden air causes headache, dizziness, and irritation of the throat and of the urinary system. If the workman is exposed for long periods to turpentine fumes, it often causes chronic inflammation of the bladder and kidneys. These fumes cause also inflammation of the skin and often affect the nervous system, as is evident in the typical symptoms of staggering and in extreme cases loss of consciousness.
Benzine and naphtha are used in hard oils as driers and very often constitute a large percentage of the vehicle in cheap quick-drying paints. Fumes from these liquids affect the nervous system much as does alcohol, causing staggering, defects of memory, and disturbance of sight and of hearing. Where the workman is long exposed to these fumes, chronic poisoning takes place, causing skin diseases, weakness, nervousness, and sometimes even impaired mentality.
Benzol is used in priming and as a paint and varnish remover because of its penetrating and solvent qualities. The benzol fumes are very dangerous and may be fatal. They cause changes in the blood, hemorrhages of the organs and mucous membranes, and degeneration of the organs. The symptoms of this poisoning are a flushed face, dizziness, and headache, followed by a blue appearance of the skin, nervous excitement, or stupor accompanied by sickness. If the poisoning is chronic, ulcers appear on the gums and lips.
Wood-alcohol poisoning comes mostly from inhaling the fumes while using Farnish. This causes headache, hoarseness, twitching of the muscles, weak heart, unconsciousness, and temporary or permanent impairment of sight even to the point of complete blindness.
Amyl acetate, derived from fusel oil and acetic acid, is used in varnishes, gilding fluids, and as a paint solvent. The fumes cause headache, uncertain movements, difficulty in breathing, sleepiness, bad heart action, and poor digestion.
Poisoning from the various paint vehicles may be avoided in most cases by insuring good ventilation, either natural or artificial, of shops or rooms where work is being done. When this is not possible, the men should be changed as often as possible on work, so that no one of them will become enough poisoned for permanent injury.
Although the vehicles in the various leadless paints are usually much more poisonous than those used in lead paint, the introduction of these paints into the industry is a great help toward the betterment of hygienic conditions in the trade, as it is much easier to avoid poisoning from the vehicle than it is from the various lead pigments in the paint.
It may be noted that the paints used in railway-car painting are almost entirely the new leadless or almost leadless kind. The smoothing of all paint surfaces is done either by the use of pumice stone and water or with oiled emery cloth or sandpaper. All paint is removed by burning and scraping, and the work is done in large open buildings, where the ventilation is such that there is very little, if any, danger from the volatile substances in the paint. Railway-car
painting in Richmond is therefore to a very large extent free from the dangers of poisoning above cited.
Economic conditions.—House and sign painters are to a very considerable extent free lances, working first for one contractor and then for another, or independently on their own account. The character of the work done by them varies greatly from job to job, and partly because of the miscellaneous character of their work and partly because of the nature of the climate in Richmond employment is not markedly seasonal. The slack season is from the 1st of January to the end of February, and the men are employed on the average about 10 months during the year. The sign painter, when weather does not permit outside work, usually has on hand work which can be done in the shop. As regards painters in the car shops and in manufacturing plants, employment is generally steady, and the seasonal fluctuations inconsiderable. Hours of labor range from 8 to 9 hours per day, or 48 to 54 hours per week, full time being worked on Saturdays. Skilled journeymen earn $3 per day, the minimum wage for unskilled labor being $1.50. Wages are low as compared with wages paid in other trades. The trade is about 10 per cent organized.
Age period of productivity.—Boys enter the trade between the ages of 16 and 18 years, and serve a four years' apprenticeship. The age period designated as the period of maximum productivity is from 22 to 55 years.
Demand for labor.-House painting is a field in which the demand for labor is increasing, but the occupation is, nevertheless, somewhat overcrowded, espe cially with semiskilled workers. The demand for sign painters is increasing, and there is a scarcity of skilled high-grade workmen. In the car shops and in manufacturing plants the demand for labor is fairly stationary. In general, the supply of medium-grade labor seems adequate for the present demand; the supply of high-grade labor is insufficient to meet the increasing demand in special lines. Workers are recruited from the lower grammar grades and from casual labor.
Educational trade and technical requirements.-In the way of general education the occupation of the painter makes no special demand upon the worker beyond that degree of general education required for all workers to insure to them advancement in proportion as they acquire in practice trade and technical excellence.
The trade and technical knowledge required by the skilled artisan is, however, very considerable. The nature of this knowledge will be apparent from the foregoing account of the processes and hygiene of the occupation. Some trade knowledge pertains even to the simplest processes, as, for example, to the process of rubbing down surfaces, where sandpaper of a proper grade of fineness must be selected, or some other material, such as ground pumice stone, rotten stone, fine steel wool, or curled hair. The painter must know which of the many varieties of fillers, sizes, or foundations should be used on woods of different qualities and in different classes of work. He must know something of the preservative qualities of different finishes. He must know how to mix oils, pigments, and varnishes for body coats, for flat and for glass finishes, for inside and for outside work. In all color work he must have a knowledge of color mixing and harmony.
The degree of manipulative skill required by the painter varies from the small amount required to lay on rough body coats to the very considerable amount required for flowing on varnishes, and for the fine work of striping, lettering, and decorating. The characteristic tool of the painter is the brush, which varies from the small round pencils and sash tools of camel's hair to the large round or flat brushes of hog bristles. In the handling of these tools a very high degree of manipulative skill is required for certain classes of work. In all classes of work the skilled hand economizes time, labor, and material.
In addition to the above qualifications, the painter should possess an accurate color sense, an artistic sense, which will enable him to harmonize colors in inside decorating, and to do original work in designing; a knowledge of alphabets for lettering, and a natural talent and skill in freehand drawing. Finally, it is vitally important that the painter shall have a thorough knowledge of the hygiene of his occupation.
What the industry gives.—The workers in the skilled class enter the trade through an apprenticeshiņ, usually of four years. During these four years the apprentice is occupied as follows. In the first year he helps by running errands and cleaning brushes, and picks up such information as he can from observing the workmen; he learns to mix paints and to rig scaffolds; he does inside and outside painting, and learns to remove stains by the use of lime and acids. In his second year the apprentice is put on the scaffold and works with the journeymen putting on finishing coats; he learns how to remove old finish by burning and scraping, or by the use of solvents, and how to prepare work for new finish. In his third year the apprentice is put on inside work, such as graining and varnishing, and is in general allowed to do such work as he is able to do. During his fourth year he is given such work as he has not already done, and by constant practice becomes more proficient in all lines of work. This apprenticeship gives the boy a small amount of trade knowledge and enables him to acquire a fair degree of manipulative skill.
No provision is made in the shops for systematic instruction either of apprentices or of journeymen. The line of promotion is from apprentice to journeymen, and from journeymen to foremen. The skilled painter may go into business on his own account.
Deficiencies of workman.-The deficiency most commonly acknowledged by the painters is deficiency in the general education which they believe to be a condition of advancement in their trade. Nearly all painters have a very inadequate knowledge of the hygiene of their occupation. Few possess the trade knowledge necessary for estimating costs and qualities of material, and few possess an adequate knowledge of the principles of color mixing, color harmony, or design.
What the school ought to give.—Before entering the shop the painter should have received in the public school a complete elementary general education and prevocational training in drawing, design, and color harmony.
A serious obligation rests upon the school, as regards instruction of apprentices and journeymen in the shops. This obligation arises from the fact that a thorough knowledge of the hygiene of the occupation is absolutely essential as a safeguard against poisoning. Such instruction, it would seem, should take precedence over every other sort of continuation work. Assuming, however, that this instruction is given, the school may properly undertake to give instruction organized with reference to the technical requirements of the painter by offering courses covering freehand drawing, lettering, design, color harmony, composition of paints, varnishes and other materials, and modern practice in special lines of work.
These courses may be grouped under the following heads (see also outline of course for painters):
1. Trade hygiene: Diseases and dangers of the trade.
RELATION BETWEEN VOCATIONAL EDUCATION AND
The most fruitful field of vocational guidance, like that of vocational education, is the public school. Vocational help will always be needed for young people outside of the schools, and for older persons who have not found themselves in life work; yet the best service can be rendered in the plastic years of school life, when courses of study and school influences may be made to contribute to the real preparation of the young person for a vocation.
Before discussing at length the place of guidance and its relation to vocational training, we may speak of the needs and conditions which have within half a decade produced the vocational guidance movement.
The age which has made a watchword of the term “efficiency” is peculiarly sensitive to all forms of waste. It calls for such training as shall eliminate waste. The conservation of our natural resources is simply another phase of the antiwaste, or efficiency movement. There is, likewise, a movement spreading through the country which looks more closely to the conservation of our human resources. This movement finds its expression in vocational guidance and vocational education, which are, in a large sense, inseparable.
While the movement for vocational education has been conspicuously advocated from the side of industry, the vocational guidance movement has been distinctively the product of present-day social service. Both movements in their present developments and in their future activities belong to the socially minded educator, philanthropic worker, and employer.
Drifting from school to work, and from job to job, is now clearly regarded as a very costly kind of human waste. Working in undeveloping employments means a waste of time and energy to the worker and a loss to society. To stop this waste and to encourage each boy and girl to plan and make the most of life are the chief aims of the vocational movement.