Time And Motion Studies Or Predetermined Times – Is One More Trusted Than The Other?

Time and motion study is a business efficiency technique combining the Time Study work of Frederick Winslow Taylor with the Motion Study work of Frank and Lillian Gilbreth. The best known experiment involved bricklaying. Through carefully analyzing a bricklayer's job, Frank Gilbreth reduced the number of motions in laying a brick from 18 to 6. Thereafter the bricklayer both increased productivity and decreased fatigue.

A predetermined motion time system (PMTS) is frequently used to set labor rates in industry by calculating the amount of time required to perform specific tasks. The first such system is known as Methods Time Measurement (MTM) released in 1948 and today existing in three variants, commonly known as MTM-1, MTM-2, and MTM-3. Another popular PMTS is the Maynard Operation Sequence Technique (MOST), which was first released in 1972.

Most predetermined motion time systems use time measurement units (TMU) instead of seconds for measuring time. One TMU is defined to be 0.00001 hours or 0.036 seconds These smaller units allow for more accurate calculations without the use of decimals.

The choice of which variation of a certain PMTS to use relations on the need for accuracy versus the need for quick analysis, as well as the length of the operation, the distinctions involved in the operation, and the repetitiveness of the operation. Longer operations often take place on a larger scale, and tend to be less repetitive. For longer, less repetitive operations, the need for a more detailed PTS is not required as much as the need for a greater based PTS such as MTM-3 or MOST.

Most production workers and a great deal of their supervisors trust a traditional stop watch time study over a PTS because it is a method they understand. The PTS is more accurate and it takes out all the calls calls of performance rating. Performance rating has to be learned through education and experience were as with PTS as long as you have the method and layout of the production work area development and modifications can be made from the desk top. Performance rating is not necessary because the PTS has the task times already leveled. Leaving a quicker / unjudgmental response time for delivering piece standards.

The downside to standard development through time studies is the amount of time to gather a wide range of operator work pace and level of experience. So the answer comes down to, time studies although are more trusted by the production floor but predetermined time systems are more accurate, does not contain judicial performance rating and provide a fast response time.