Fatigue study

by Frank B. Gilbreth; Lillian Moller Gilbreth

Types of Chairs and Their Uses.

We are fortunate in that, of the nine chairs exhibited, each represents quite a different type. This illustrates the large field for chairs.

[Chair No. 1] is designed for work to be done standing or sitting. This is the ideal fatigue eliminating chair, as it allows of the most scientific distribution of work and rest periods, and for the greatest variation in working periods. The work for which this chair was devised was the folding of handkerchiefs, work that had always been done sitting. This chair is the result of accurate measurement, and is of exactly that height that will permit the girl’s elbows to be at the same distance from the work table when she is seated as when she is standing. The back of the chair, like the backs of all chairs designed for eliminating fatigue while working, is designed for work and not for rest. The chair is provided with dome casters, which allow of its being pushed away, or drawn back into position with the least amount of time and effort possible. The worker on this chair has a foot-rest which is a part of the working table.

Fig. 12
This chair is of type one, devised for doing work that has always been considered sitting work, either standing or sitting. In this case an ordinary chair has been boosted so that a worker can sit at a work-bench made exactly the right height for standing work. The chair is provided with ball-bearing casters, so that it can be pushed out of the way or pulled into position with little effort. This device helped make it possible to divide each hour into work periods and rest periods; and at the same time into standing and sitting periods,—thus not only eliminating unnecessary fatigue, but providing an efficient means for recovery from necessary fatigue.

Fig. 13
This chair is of type two, devised for doing work that has always been considered standing work, either standing or sitting. By its use, heavy filing can be done with greater ease and with the same speed and efficiency. The chair is inexpensive and easy to construct, and is of such a height as best suits the individual worker.

Fig. 14
Another view of the chair as shown in [Fig. 13]. The projecting foot-rest on this chair enables a man to push the file as efficiently and more comfortably seated than standing.

[Chair No. 2] is devised in order that a kind of work which has always been done standing may be done sitting. The work is heavy filing done at a vise, and the chair is provided with a projecting foot-rest. The work-bench is of such a height that the man may work either standing or sitting. In actual practice the filer works half of the time sitting, and half of the time standing.

[Chair No. 3] is designed to eliminate vibration of floors that carry much high-speed machinery. An ordinary chair is provided with springs, that relieve the operator of one hundred per cent. of the vibration of the floor. This chair was designed for work at a machine, and the operator is provided with a foot-rest, which rests on felt to kill the vibration. Note also the verandas on two sides of the chair for foot-rests.

The [fourth type] of chair is also a shock absorbing chair, which is more complicated in its construction.

The fifth type of chair is designed for school work, and has a rest for the right arm that may be lowered or put in place.

The [sixth type] of chair is a modification of a chair already in use. A chair which was once, perhaps, fairly comfortable has become worn off from years of use. This is rectified by boring holes in four small blocks of wood, and fitting them to the legs of the chair, which brings the chair back to its originally desired height. A well-known Middle West manufacturer used iron piping for the same purpose as the four blocks of wood. This is, in some cases, easier to secure, although not so good for the shop flooring.

A seventh type of chair is an adjustable, telescopic stool, which the inventor claims is adaptable to both factory and office work. This is admirable in that it allows of the chair being adapted to some degree to its user at the expenditure of little time or money.

Fig. 15
A worker using the filer’s chair, shown in figures [13] and [14].

Fig. 16
This chair is of type three, designed to eliminate fatigue from surrounding conditions. An ordinary chair, which was fairly useful and comfortable, was provided with springs that relieved the operator of 100 per cent. of the vibration of the floor. It is to be noted that the device attached to the chair is extremely simple and inexpensive, while at the same time it solves a problem that has always been rated as most difficult.

The eighth type of chair is devised for rest periods. We have two examples of this. One is a small folding stool contributed by a local drygoods merchant, much interested in fatigue elimination, who, as a result of our fatigue eliminating campaign, has installed many of these stools in his large store. The other is a more complicated chair with adjustable seat and back. This is designed not only for causing least possible fatigue, but also in the interests of correct posture of the user.

Four of the chairs show particularly what can be done with little expenditure of time or money. Only the filing chair is a “new” chair, in the sense of the entire chair having been made especially with the idea of fatigue elimination. The other three chairs consist of chairs already in use, supplied with cheap adjustments, made of material already at hand. These may impress the reader as extremely inartistic. This they undoubtedly are, but these are chairs of the transitional period, made to better working conditions immediately, and to be used until standard methods are introduced, and new standard fatigue eliminating devices substituted. It must also be noted that three out of the four chairs are provided with what are practically footstools, although only one is shown in the picture, as only one is attached to the chair itself. The fourth chair allows of the feet being placed comfortably on the floor.