Standard Operating Procedure (SO ...

The principles of motion economy can be classified into four groups:

Use of Human Body

• The two hands should begin motions at the same time.
• The two hands should not be idle at the same time except during rest periods.
• Motions of the arms should be made in opposite and symmetrical directions and should be made simultaneously
• Hand motions should be confined to the lowest classification with which it is possible to perform the work satisfactorily:

1. Finger motions
2. Wrist motions
3. Forearm motions
4. Upper arm motions
5. Shoulder motions

• Momentum should be employed to assist the worker whenever possible, and it should be reduced to a minimum if it must be overcome by muscular effort.
• Smooth continuous motions of the hands are preferable to zigzag motions or straight-line motions involving sudden and sharp changes in direction.
• Ballistic (i.e. free swinging) movements are faster, easier and more accurate than restricted or controlled movements.

Arrangement of the Work Place

• There should be a definite and fixed place for all tools and materials.
• Tools, materials, and controls should be located close in and directly in front of the operator.
• Drop delivers should be used whenever possible.
• Materials and tools should be located to permit the best sequence of motions.
• Arrange the height of the workplace and chair for alternate sitting and standing, when possible.
• Provide a chair of the type and height to permit good posture.

Design of Tools and Equipment

• Combine tools whenever possible.
• Preposition tools and materials.
• Where each finger performs some specific movement, the load should be distributed in accordance with the inherent capacities of the fingers.
• For light assembly, a screwdriver handle should be smaller at the bottom.
• Momentum should be used to help the worker in doing their task not to increase their task.

Time Conservation

• Even a temporary delay of work by a man or machine should not be encouraged.
• Machine should not run idle, it is not desirable that a lathe machine is running and its job is rotating but no cut is being taken.
• Two or more jobs should be worked upon at the same time or two or more operations should be carried out on a job simultaneously if possible.
• Number of motion involved in completing a job should be minimized.