ERGO-MTM model: an integrated approach to set working times based upon standardized working performance and controlled biomechanical load

Abstract

ERGO-MTM is an innovative model to set standard times of manual tasks. MTM, developed in the forties by industrial engineers, assigns a basic time to execute a given motion based on the concept of normal performance (speed, effort and precision). The traditional models to set a standard time then add to the basic time a fatigue allowance, applied on each individual motion, depending generally on the type of posture and on the load/force implied in the motion. To the light of the most recent ISO/CEN standards dealing with biomechanical load, the traditional models do not meet the requirements any more: it becomes mandatory to consider the load generated by the overall assignment of working tasks to a workstation to be compliant with the new ergonomics standards. ERGO-MTM is the solution: it determines a fatigue allowance (named Ergonomic Allowance), which is applied on the total workstation basic MTM time to allow the necessary recovery periods, enough to keep the biomechanical load within safety limits. The final result is a standard time based on a norm level of performance and a work sequence with a controlled biomechanical load.