WFC Times blauw0202

what is it?

Standard elements

Factors of influence


what is it?

Basic elements


and effective

WORK-FACTOR, WF, is a detailed system of Method study and Time study for analyzing the actions and motions of workers. It is a system of pre-determined times, also called a P.E.M.T.S., Predetermined Elemental Motion Time System.

The system is based on the pioneering work of Frank B. Gilbreth, who pointed out that all human work, both traditional or working with machines, basically consists of the same ever returning elementally movements, the so-called "standard elements".
Conversely, using these standard elements, it is therefore also possible, to determine in advance the necessary motions for a particular acitivity.

By building and structuring the WORK-FACTOR system, researchers searched for and discovered the different factors that influence the time of these standard elements, the so-called "factors of influence", and measured the delay of time for each factor of influence and expressed this in an unambiguous unit of time delay, the Work-Factor, wf, and they indicated the value of the time delay by a number of wf’s.
These factors of influence and the number of wf’s therefore give information on the degree of difficulty of a particular motion. Decrease of this degree of difficulty means decrease of the physical and/or mental load. And with that often a decrease of the necessary time also. The system provides therefore clear information on the possibilities to adapt the work to the physical and mental qualities of the human being i.c. the operator (ergonomics) and on the possibility to apply aiding tools or mechanization sensibly.

MENTO-FACTOR, MF, is a detailed system of Method study and Time study for analyzing mental work or mental processes of workers, like focussing the eye, inspecting, interpreting and deciding, calculating, resulting into (a certain way of) physical action.
This system makes it possible to analyze controlling -, reading -, calculating -, counting - and reaction processes and to determine the correct working method for it.

MENTO-FACTOR is, just like the other WORK-FACTOR systems of pre-determined times, constructed from basic or standard elements with factors of influence.

MENTO-FACTOR deals with the intake of information by one of the senses i.e. eye, ear, taste, smell or touch, transforming the information into impulses which are guided via the nerves to the brains, where recognition of the information and organization of the correct reaction to the information takes place and subsequently guiding it again via the nerves to the muscles of the limbs or back to the senses for purposes of taking further information.

Only in cases of the mental proces taking more time than the time for the physical motion or the mental process actually taking place after a physical action, like checking an object on dirt, scratches, correct colour or indentations, the corresponding time must be analyzed.

WORK-FACTOR and MENTO-FACTOR aim at optimally tuning operators and means to one another, meaning ergonomically and efficiently. Therefore they are valuable and powerful instruments for designing, fitting and controlling labour systems, like men - machine systems.