Fig. 6. How one company utilizes its rest period to promote good posture. on output, is certain. In material furnished the Bureau, Mr. Spaeth gives one instance of the reorganization of a pressing department, where the women had been standing at their boards all day. Mr. Spaeth not only introduced rest periods of five minutes' duration at 10 a. m. and 3 p. m., but saw that comfortable chairs were provided for use during these periods. The result was that an average gain in efficiency of 20.3 per cent was made by a group of four skirt pressers who were studied before and after the introduction of these rest periods. Without rest periods, the average efficiency of the four operators for nineteen days was 70.2 per cent; with rest periods, the average efficiency of the same group for nineteen days was 90.5 per cent. Undoubtedly this astounding increase in efficiency was due to psychological factors, as well as physiological ones, but the fact is undisputed that a plan enabling workers to change their positions at intervals during work hours, has a definite and often startling effect on output. The arrangements which are to secure this possibility of change whether they be rest periods, interchange of process, regulation of supplies, or what not, must of necessity vary in different plants. However, with foresight and the use of a little imagination, change of position becomes not only practical but comparatively simple. SEATS FOR USE DURING REST PERIODS A good chair for rest is one which can afford relaxation from the position which has been necessary while working. When the work has been done in a standing position, the rest chair should allow the operator to stretch out and relax completely. With the automatic rest period, where the operator cannot go far away from his work, or where the aisles are crowded and no rest room is provided, a chair that will not take up too much space is necessary. Even in such a case, the chair must insure to the worker back support and a reasonable degree of comfort. Stools, so often used for automatic rests, are never acceptable. Besides the necessity for variation in posture, we have the second important principle: that conditions should be such that good posture is possible during work hours. WHAT GOOD POSTURE IS In defining good posture, the Bureau is taking as authoritative, statements from the American Posture League and from Dr. Joel E. Goldthwait, orthopedist of Boston. Good standing posture "One in which the different segments of the body-head, neck, chest and abdomen are balanced vertically one upon the other so that the weight is borne mainly by the bony frame-work and a minimum of effort and strain is placed upon the muscles and ligaments. In this posture under normal conditions the organic functions - respiration, circulation, digestion, etc. are performed with least mechanical obstruction and with greatest efficiency." (American Posture League.) Good sitting posture-" The thing which should always be insisted upon in the use of the body in any way is that the body should be kept straight from the hips to the neck and should not be allowed to flex or bend at the waist line. Any position which allows this lowers the vitality of the individual, leads to strain of the back, and naturally lessens the efficiency of the worker." (Dr. Goldthwait.) CORRECT WAY OF LEAN- WRONG WAY OF LEAN- Fig. 7. In correct position leaning forward, the feet should rest comfortably on the floor or foot rest, the body should be kept straight from the hips to the neck and the inclination forward should occur entirely from the hips. EFFECTS OF BAD POSTURE Two postures most commonly assumed and most detrimental to health are the sideways slouch and the slump or stoop shoulder posture. There is a wide variance of medical opinion regarding the effects of bad posture on health, from the statement that bad posture checks CORRECT WAY OF LEAN- SLUMP SITTING Fig. 8. In correct position leaning backward, the feet should rest comfortably on the floor or foot rest, the pelvis should be as close to the back of the chair as possible, to prevent sliding forward, and the small of the back should be supported. the normal functions of the body to statements that attribute to wrong posture predisposition to a wide variety of diseases. "The habits of posture that pro duce round shoulders and forward drooped head not only lessen the space in the chest for the lungs, but may inflict great injury upon the organs within the abdominal cavity. While a variety of conditions are active in the production of a downward displacement of the organs, this bent forward posture of the body, especially in individuals of tall and slender build, is conducive to it. Normal folds-and turns in the digestive tube are deepened by the folding inward of the wall of the abdomen on the belt line, and by the downward crowding that takes place. The canal is thus partially closed in places, with consequent damming back of its contents, thereby giving time for the colonies of bacteria always in residence there, to multiply and the toxins they produce to be carried into the tissues of the general body in excess of elimination. As a result, constipation, diarrhea, flatulence, disturbances of circulation, headaches, nervous irritability, and most marked of all, fatigue out of proportion to effort expended, lessen the efficiency of the indivdual and often make life a burden." 1 In the sideways slouch position the weight is more on one foot than on the other in standing, and more on one hip than the other in sitting. "The ribs are crowded together between a low shoulder and a high hip on the one side, and proportionately separated upon the other side, between a high shoulder and a low hip. The wide separation of ribs on the high shoulder side limits their motion and thus interferes with the entrance of tidal air, especially at the apex of the lung on that side. The tubercle bacillus seems to find a good place for growth and multiplication in this region; certain it is that in a large number of persons suffering from tuberculosis this posture is the habitual one and the disease first invaded the apex of the lung on the side of the high shoulder." "In girls and women, with the marked slouch habit, the fundus of the uterus is almost invariably found lying beyond the median line of the body toward the high hip side, crowded over by the intestines which fall into the larger space on the low side." 1 1 Mosher, Eliza M. Relation of Posture to Health. New York. American Posture League. 1917, p. 4-5. PART II SEATING IN INDUSTRY The posture of the worker is directly affected by innumerable working conditions such as lighting, the speed of the operation, the clothes the worker wears and so forth - but no single factor has so great a share in producing bad posture as the use of the ordinary factory seat, and the failure to take into consideration the relationship of that seat to the other parts of the work place. "The average factory chair," says Mr. Frank B. Gilbreth, "reminds me of the time-worn story of the coffin: the man who made it, didn't want it; the man who bought it, didn't use it; and the man who used it, didn't have much to say about it."" Fig. 9. Such an arrangement is no more than "out of the frying pan into the fire." "In our own experience we have found it wise to observe most carefully indications of discomfort on the part of the operators. When stools are found with boards nailed on to provide a crude support for the back; when old boxes or broken chairs are being used under the benches for foot rests, we may be certain that the plant is not being operated at a maximum of physiological efficiency." "It takes an agile operator to reach the top of a stool like that shown in Fig. 10; and it takes an enormous amount of energy to balance there for a day's work. To sit with feet dangling is impossible for any length of time, and the usual defense on the part of the worker is to brace him self by hooking his feet about the table or stool leg or wedging his thighs between the table and stool top." Such stools may be cheap in purchase price, but they are expensive in the long run. It is no wonder that after a succession of working days spent on seats such as these in Figs. 10, 11 and 12, with no relief afforded by change of position or rest periods, we find workers who are unable to relieve their tired muscles in any other way, taking peculiar positions which we call slump" or "round shouldered." These positions soon become the most comfortable ones simply 66 Fig. 10 FIG.12 Figs 11, 12.- In these chairs the back supports extend to the seat, allow no open space, and when the worker sits back, they tend to push the body forward into the hollowed center of the seat. The "slump" position is inevitable. because the over-fatigued muscles have deteriorated to such an extent that they are incapable of supporting the body in a normal position for any length of time. THE RELATIONSHIP OF PARTS OF THE WORKPLACE To provide a good chair for work is only one part of the job of making a comfortable position at work possible. The relation of the different parts of the work place (the bench, chair, foot rest, the place for supplies and the place for finished work) is vitally important. The bench or chair may be too high or too low. A brace or bar or set of drawers reaching from the bench top to the floor may prevent a comfortable position of the worker's feet and legs. In the packing department of a large plant the management decided to replace stools with chairs of superior type. The manager showing a visitor through this department pointed out the new chairs. Apparently none of the chairs were in use, for the workers were standing. It turned out that |