What are "Therbligs"?

Question

Accepted Answer

The correct option is 1:
Therbligs are a cornerstone concept in industrial engineering and motion study, introduced by the pioneers of time and motion study, Frank and Lillian Gilbreth. The term "Therblig" is a clever near-reversal of the Gilbreth surname. This classification scheme was developed to break down any manual work or industrial task into a series of fundamental, irreducible elemental motions. By classifying all possible hand and body movements into one of these 17 basic categories—such as Search, Find, Select, Grasp, Position, and Assemble—industrial analysts can precisely measure and optimize the efficiency of a worker’s movements. The ultimate goal of this detailed analysis is to identify and eliminate non-productive motions, thereby increasing worker productivity, reducing fatigue, and standardizing the "one best way" to perform a task.

The incorrect option is 2:
The Mayer's classification scheme of material handling is not the correct identity of Therbligs. While material handling is an important topic in operations management, dealing with the movement, storage, control, and protection of materials, Therbligs are a highly specific, micro-level tool. They are exclusively focused on the elemental movements of a single worker's hands and body to achieve maximum efficiency at the workstation level.

The incorrect option is 3:
The Mayer's classification based on shop floor level is an irrelevant concept in the context of Therbligs. The purpose of the Gilbreth's Therbligs is the analytical breakdown of human motion to eliminate wasted effort and fatigue, applying to any task or level. The categorization or management of the "shop floor level" relates more broadly to layout, supervision, and process flow, which is conceptually distinct from the minute analysis of a worker's basic hand movements.

The incorrect option is 4:
The Fayol's classification for span of control is completely unrelated to the concept of Therbligs. Henry Fayol was a classical management theorist known for developing the 14 Principles of Management and for his administrative theory. Span of control specifically refers to the number of subordinates a manager can effectively supervise, which is a fundamental principle of organizational structure and management hierarchy. It has no connection whatsoever to the analysis of a worker's physical movements at the operational level.