Friday, September 29, 2017

MOTION STUDY VARIABLES - Frank B. Gilbreth - Part 3



That previous experience is an element to be considered is obvious. This fact is so well recognized that the expression "You can't teach an old dog new tricks" may be heard around the world. While this may be true with dogs, it is not true with workmen. On a short job it may not be advisable to attempt to change radically the life-time customs of a local workman. But recording the output of each man separately will tell whether or not it is advisable to make out the instruction card in accordance with the previous experience of the workman, or in accordance with the way in which actual records have proved to be productive of the highest outputs. Experience varies widely, and the habits formed are often difficult to overcome.

Example. A bricklayer from certain sections of New England has been accustomed to pick up mortar with a trowel at the same time that he picks up brick with the other hand. This is called the " pick-and-dip method." The size and shape of his mortar receptacle, the arrangement of the brick and mortar on his scaffold, the shape of the scaffold itself, the sequence in which he builds the
vertical tiers and the horizontal courses, and, finally, the labor- union rules themselves, are fashioned after the consequences of using a small trowel, just large enough to pick up sufficient mortar for one brick only.

A bricklayer so trained finds it difficult at first to adapt himself to the " string mortar" method of the West. The western-taught bricklayer experiences the same difficulties in adapting himself to the " pick-and-dip " method with the speed of the eastern bricklayer. But their difficulties are nothing compared with those that the employer experiences who puts the good points of both systems on
any one job.

Not only do habitual motions become fixed, but also the previous experience of the bricklayer is often the cause of his making too many motions, i.e., unnecessary motions. He seldom, if ever, has been rigidly trained to use a certain number of definite motions. It takes time and patience to induce him to adopt a standard method.

On a small job it is advisable to select those men for the leads and the trigs who are best fitted to be leaders, that is, who are best prepared by previous experience to carry out without delay the requirements of the instruction cards but give due consideration to the previous experience and habits of work of the workmen.

On a large job, however, it is most economical to insist on standard methods and standard motions that will produce the highest outputs, without regard to the previous training of the workmen. Attract and retain those workmen who can follow out their instruction card and as a result produce the high records of outputs.


Fatigue is an important variable to consider when selecting those motions that will give the most economy and that make the " standard motions." It goes without saying that the motions that cause the least fatigue are the most desirable, other things being equal.

Fatigue is due to a secretion in the blood. To quote from an article signed "I. M. T." in the
American Magazine for February, 1910:

"The toxin of fatigue is the phrase the physicians have given us with which to jar the attention of those who can only be stirred by harsh words. It has been demonstrated in the last few years that fatigue is due to an actual poison not unlike the poison or toxin of diphtheria. It is generated in the body by labor. But the system takes care of itself and generates enough anti-toxin to take care of a normal amount of toxin or poison. If it continues to be produced in abnormal quantities the system cannot grapple with it. There is a steady poisoning of the body, with all the baneful effects, mental and moral, as well as physical, that poison produces."

Continuous hard work, however, like proper training, puts the body into that condition that best overcomes fatigue. Fatigue is due to three causes:

1. Fatigue due to coming to work improperly rested (fatigue brought to the job).

2. Unnecessary fatigue, due to unnecessary work, unnecessary motions, or uncomfortable positions, surroundings, and conditions of working.

3. Necessary fatigue, due to output.

Every motion causes fatigue. The same motions in the same trade cause about the same fatigue for all first-class men, and they all require about the same amount of rest to overcome fatigue, provided their habits and mode of living are the same outside of working hours.

The amount of fatigue caused and the percentage of rest required in many different kinds of work have been computed by Frederick W. Taylor with great exactness. He has assigned the various workers to classes and accurately computed the "task" from his records.

We have no such records as Mr. Taylor has gathered, but we have numerous records of outputs of different men on several kinds of work. We know that the amount cf rest actually required by a workman increases with the discomfort of the position in which he works. We also know that the speed, hence the output of the worker, decreases rapidly if there is much fatigue to overcome.

Example. A bricklayer can lay brick for a few minutes quite as quickly when he picks up the brick from the level of the platform on which he stands (see Fig. 9), as he can when he picks up the brick from a bench twenty-four inches above the level of the platform on which he stands (ses Figs. 10, n, and 12), but he cannot keep that speed up, because he requires more rest to overcome the greater fatigue.

It is not simply for the welfare alone, although that reason should be sufficient, but for economic reasons as well, that the men should be so placed and equipped that their work is done under the most comfortable conditions.

Examples. i. It is a recognized fact that a cluttered-up floor under a workman's feet will tire him quite
as much as the productive work that he is doing. A smooth-planked floor will enable a bricklayer to lay many more brick than will earth that has been leveled off.

2. A bricklayer can stoop over and pick up anything from the floor with one hand with much less fatigue if he has a place to rest his other hand while he is stooping, because he puts his weight on one foot and lifts his other foot out behind him, which does not tire the muscles of his back nearly so much.

Slow motions do not necessarily cause less fatigue than quick motions, and, per unit of work done, may cause much more fatigue than quick motions.

The amount of work done per motion may not be fatiguing proportionately to the size of the unit.

Example. - Lifting ninety pounds of brick on a packet to the wall will fatigue a bricklayer much less than handling the same number of brick one or two at a time. Consequently with the same amount of fatigue the workman will handle several times as many brick on packets as he can handle one or two at a time.

We have, then, under this variable two tasks to perform:

1. To eliminate unnecessary fatigue. This we do by studying and fixing the variables; that is, by standardizing the work.

2. To provide for rest from necessary fatigue, and to utilize rest time.

Under old forms of management workmen " should keep busy at something," even if prevented from doing their regular work. An idle workman was considered a disgrace. The consequence of this was that the workman took his rest while working, or made believe work while resting. The old-fashioned kind of rest is called " systematic soldiering." It is the curse of the military type of management. It is
a form of cheating that has been made respectable by the conditions forced upon the workers by the employers.

Under scientific management the evils of soldiering are eliminated, and the correct definite  percentage of rest required is recognized and provided for. When a man is prevented by causes beyond his control from doing his regularly assigned work, he is told to use the opportunity
for rest, not to take such rest as can be obtained by making slow and useless motions, that will give him an industrious appearance to the casual observer, but to rest, the 100-per-cent kind of rest.

There are cases where chairs and reading tables have been provided with beneficial effect for workers to occupy when delayed for a few minutes. They get the rest, and their presence at the table acts as a danger signal to the management.

When a man is fatigued to the point where it is impossible for him to do his best work he should be made to rest. He must not do anything but rest until he is in that condition that will enable him to fly at his work and perform it with the fastest standard motions possible.

Rest does not necessarily mean idleness. The worker can spend the rest period reading his instruction card, or filling out his record of output on the card, or in some other form of restful work. A change of work is often a rest. By performing the above two tasks well, we secure the greatest output per day and the fewest hours per day without injury to the health of the men.


The habits of the workman have much to do with his success in eliminating unnecessary motions and in adopting quickly and permanently standard methods. The term ''habits," as here used, includes not only personal " habits," so-called, but also habits of thinking, habits of working, etc.

Habits brought to the work may act as a deterrent or as an aid to its best performance. They embrace a group of sub-variables which are difficult to describe and analyze, and are of immense importance in influencing output.

That acquiring good habits of work makes the worker more versatile as well as more efficient is forcefully stated by Mr. Gantt in his book on "Work, Wages, and Profits."
He says:

"The habits that a man has to acquire to become efficient in one class of work stand him in good stead in becoming efficient in other work. These habits of work are vastly more important than the work itself, for it is our experience that a man who has become efficient in one thing, readily learns to become efficient at doing other things."

The health of the worker may be affected by:

1 . Other things than his work and the conditions under which it is done.

2. The work.

Consideration of other things than the work may properly be left to the welfare department. This department can most successfully define the scope of its work by attempting to improve the man himself and his surroundings in every way that will make him a better and more successful worker. This criterion will satisfy both employer and employee as to the appropriateness, justness,
and utility of the work of the welfare department.

The life of the man when away from work is only in so far subject to the inspection and jurisdiction of the so-called "welfare" department as that department can show itself able to make of the man a more valuable economic unit to himself and to the community.

If the welfare department makes an efficient workman the product of its work, the philanthropic by-products will take care of themselves.

The work itself should be laid out in such a way that its performance will add to and not subtract from health. A proper study and determination of the variables that affect the surroundings and the motion will go far to insure this. Moreover, standardized work will transform the workman.

Henry L. Gantt, in a most stimulating paper on "Training the Workmen in Habits of Industry and Cooperation," read before the American Society of Mechanical Engineers, December, 1908, says of workmen:

"As they become more skilled, they form better habits of work, lose less time, and become more reliable. Their health improves, and the improvement in their general appearance is very marked. This improvement in health seems to be due to a more regular a-nd active life, combined with a greater interest in their work, for it is a well-known fact that work in which we are interested and
which holds our attention without any effort on our part, tires us much less than that we have to force ourselves to do."

This Mr. Gantt says in speaking of the benefits of the "task and bonus" system; but the same thing is undoubtedly true of men working under standards derived from motion study.


Mode of living has been more or less touched upon under " health" and " habits." It is a complex variable, difficult to analyze and difficult to control. Its effects on output are for this reason all the more far-reaching and demand scientific investigation.


This is a subject that has been investigated much more scientifically with regard to horses and mules than with regard to workmen, but cases are seen on every hand where it is more profitable to furnish the most nutritious food to the men gratis than to permit them to have the usual poor food of the padrones' storehouse. In the building of a new town in Maine it was found to be economical to spend considerable sums of money for supplying food for the men at less than cost, rather than to have them eat the food provided by the local boarding houses. The nutritive value of various foods and the amount of energy which various diets enable one to put forth have been made a study in training soldiers. There must be many data available on the subject, and the government should collect them and issue a bulletin for the use of the welfare departments of large employing organizations. The army might also serve as an example in many other ways to the student of economics. The " Tactics" are admirable "instruction cards," conforming to many of the laws motion study. It seems unfortunate that the governments of the world up to the present time have confined all of their attempts to standardize motions to the arts of war, and have done nothing in this line in the arts of peace.


Size of men, with relation to their motions, has much more influence than is usually realized.

Short men are usually the best shovelers where the shovelful need not be raised much in doing the work, such as in mixing mortar and concrete. Few foremen realize that this is because a short man does fewer foot-pounds of work in doing the same amount of shoveling. On the other hand ; when men are shoveling in a trench, the taller the men, usually, the more the output per man.

Oftentimes a staging is built at a height below a set of floor beams that enables the men to work to best advantage. On such a staging men should be selected of as nearly the same height as possible.


The workman with the most skill is usually the one who can adapt himself quickest to new methods and conditions.

Example. A bricklayer who has great skill in his trade can instantly lay a brick in the same manner that he is once shown. To get him to do so constantly when not supervised is difficult, but that can be quickest impressed upon his mind if he is shown the reason for every change demanded of him.

To make sure that the worker of the future acquires his skill properly, is the most important task here. This can be done only by insisting continuously on conformity to scientifically derived standards from the beginning of his training.

Example. The best results from a motion- study standpoint can be attained only by teaching the apprentice from his first day to lay the brick with the standard motions regardless of the looks of the work. If the work is not good enough to permit the brick to remain on the wall, a skilled bricklayer should fix it, until the apprentice can lay the brick with the prescribed standard motions in a manner good enough to permit the work to remain as a part of the structure.

The apprentice should not be permitted to depart from the standard motions in any case until he has first acquired them as a fixed habit. The most pernicious practice is the generally accepted one of first having an apprentice do perfect work and then attempting to make speed later. The right motions should be taught first, and the work taken down and rebuilt until it is up to standard quality. This is the only way to get the full benefits of the economics of motion study. (See Figs. 13 and 14.)

The workman who will make the highest outputs of the future will be he who has as a habit those standard motions that are the most productive when operated under standard conditions.


The temperament of the man has more to do with the motion he uses than one usually supposes.

Example. Many expert face bricklayers would quit a job rather than lay common brick on interior walls, even though they might earn higher wages on the inside work. Other bricklayers prefer to lay common brickwork, not that they doubt their ability to lay the face brick, but because they like the strenuous athletic contests for high scores of output and high pay. To them there is no monotony in laying common brick day after day, for to the skilled mason brick are not so nearly alike as are human

A bricklayer interested in his work will often remember the characteristics of one certain brick years after he has forgotten the wall upon which it was laid.

Therefore the temperament of the man must be taken into consideration when placing the men. When they are best placed they follow their instructions on the subject of motion, and higher scores will be the result.


" Training" is so closely related to "skill" and "experience" that it is difficult to separate it from them. We use the word to mean both the worker's theoretical and practical equipment for his work, his entire preparation. The problem is to see that the worker has both kinds of equipment, acquired in the most useful, balanced method possible.

The training of the available worker must always be considered in estimating the time that it will take him to acquire standard methods and the output that can be expected of him. The training of the worker of the future should be planned to fit him for standard work. The training of the apprentice on the work to-day is usually defective because he has little or no training in theory at the same time that he is getting his practice. Furthermore, the journeyman who is his instructor not only has had no training in pedagogy, but often lacks the benefits of the elements of a common-school education. The usual time of apprenticeship in the building trades in this country is three years, or until the apprentice is twenty-one years old.

On the other hand, the boy taught in the trade school lacks training under actual working conditions. The question of dollars and cents to make for the employer, special fitting for high wages for himself, and the knowledge of the principles underlying the requirements necessary in order to obtain specially high outputs from intensive management, are wholly lacking.

The present apprenticeship system is pitiful and criminal from the apprentice's standpoint, ridiculous from a modern system standpoint, and there is no word that describes its wastefulness from an economic standpoint.


Before turning to the variables of the surroundings, it may be well to summarize. The variables of the worker consist of the elements of the equipment that the worker brings to his work, both those that he was born with and those that he has acquired. These are mental and physical.

We have concluded:

1. That first-class men should always be secured if that be possible.

2. That everything possible should be done to preserve and to add to the natural powers and capacities that the worker brings to his work.

3. That standard practice derived from motion study does add to the natural powers of the worker, and both shortens his hours of work and adds to his output.

4. That training based on the laws underlying standard practice will enable the worker of the future to attain still higher efficiency and output.

Please Give Your Comments.

What is the relevance of Gilbreth's initial writing on Motion Study today?
What are new developments in this area?
What are new scientific discoveries related to human effort productivity?
What are new developments in human effort productivity engineering?
What are new development sin human effort productivity management?

Updated 30 September 2017, 19 August 2015

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