The Relation of Fatigue Study to Measured Functional Management.
Fatigue study is founded on measurement. This makes it an integral part of measured functional management. This is management that acts in accordance with standards. These standards are derived by actually measuring accurately what is happening. Standards contain the results of the measurement combined into new working methods. These standards are maintained only until they can be improved, when the new ones are in turn measured and maintained. Such accurate measurement demands that the problem of management be divided into measurable units. These units are made as small as possible, and constantly smaller as time goes on. It was the great work of Doctor Taylor to divide an operation, that is, a piece of work to be measured, into units for timing with a stop watch, and to separate rest units from work units.
From its beginning, Scientific Management has recognized the importance of the part played by fatigue. This recognition helps to obtain that co-operation and permanent beneficial efficiency that are the underlying ideas and the maintaining forces in this type of management. But fatigue study has only recently been acknowledged as fundamental to the most efficient management. Any one can attack the fatigue problem in its present condition in the industries successfully. He has simply to apply measurement. He can do this without regarding the investigations and results of others, if he chooses, but he will progress faster and farther if he uses results already at hand, and improves on “the best that has been known and thought in the world.”
Relation of Fatigue Study to Motion Study.
Motion study has been described as the dividing of the elements of the work into the most elementary subdivisions possible, studying and measuring the variables of these fundamental units separately and in relation to one another, and from these studied, chosen units, after they have been derived, building up methods of least waste. It is through the measuring of motions that one comes to realize most strongly the necessity of fatigue study.
There has come, in the past twenty-five years, a strong general realization that the important factor in doing work is the human factor, or the human element. Improvement in working apparatus of any type is important in its effect upon the human being who is to use the apparatus. The moment one begins to make man, the worker, the centre of activity, he appreciates that he has two elements to measure. One is the activity itself. This includes the motions, seen or unseen, made by the worker,—what is done and how it is done. The other is the fatigue. This includes the length and nature of the interval or rest period required for the worker to recover his original condition of working power.
Any one who makes real motion study, or analyzes motion study data, cannot fail to realize constantly the relationship of motion study to fatigue study. The fatigue is the more interesting element, in that it is the more difficult to determine exactly. When we recognize this close relationship between motion study and fatigue study, we see that we have a body of data already collected and at our disposal. What is even more desirable, we have a method of measurement ready at our hand. Every observation of a motion may be used to give information about fatigue. Is this information of immediate use to the man who is attacking his fatigue problem for the first time to-day? Yes, and no. Yes, in that it is at his disposal. No, in that he must determine his own particular problem before he can start to solve it. The first step in this direction lies in classifying fatigue.
The Classes of Fatigue.
There are two classes of fatigue:
1. Unnecessary fatigue, which results from unnecessary effort, or work which does not need to be done at all. A typical example of such work is that of the bricklayer, who furnished one of the first subjects for motion study. Any one who has watched a bricklayer lift all of his body above the waist, together with the bricks and mortar from the level of his feet to the top of a wall, cannot fail to realize that bricklaying requires a great amount of energy as well as skill. Yet by far the most of the energy expended in the method of laying bricks, that had existed for centuries, was entirely unnecessary.[2]