ERGO-MTM MODEL: AN INTEGRATED APPROACH TO SET WORKING TIMES
Work measurement is definitively a difficult task, since we miss a clear and objective reference as for distances and weights, where we have the meter and the kilogram. To set a standard time of a given man-ual task the following steps are necessary:
– Set a basic time
– Determine the proper time allowances
– Add allowances to the basic time to set a stan-dard time
A basic time is the time necessary to an average person, well instructed, moving at an average speed and paying an average effort to accomplish a task, under the hypothesis to work for an entire shift (ap-prox. 8 hours). These conditions (skills, speed and effort) merge into a factor named working perform-ance. When setting a basic time of a task with a time study, the analyst has to levelthe observed time using the normal performance as a reference (if the rated performance is higher thanthe normal performance, then the basic time would be longer than the observed time). For example, to calculate the basic time to walk 1 km, it’s necessary to observe a person walking 1 km, rate the performance and take his/her actual time to execute the task . Imagine that the stop-watch time is 800 s and that the rated performance is 110% (10% above the one of an average person walking without getting short of breath). The standard time to walk 1 km then would be 800 s x 1.1 = 880 s. If a person takes 880 s to walk 1 km, his/her performance would be exactly 100%.
