23-Ind-A2 Analysis and Design of Work · December 2018
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
National Exams — December 2018 — 17-Ind-A2 Analysis and Design of Work. Three-hour, closed-book exam (approved Casio/Sharp calculator only); any five of the seven questions constitute a complete paper and only the first five answered in the answer book are marked — all seven are solved below for completeness.
Reference texts: Niebel & Freivalds, Niebel’s Methods, Standards, and Work Design (13th ed.) — operations analysis and process charting, principles of motion economy, multiple-machine assignment, stopwatch time study, performance rating and allowances, predetermined time systems (MTM/MOST), work sampling, and job evaluation / wage-incentive systems.
Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.
MTM is a predetermined motion-time system (PMTS): it decomposes any manual task into a sequence of basic, fundamental motions — reach, move, turn, grasp, position, release, disengage, and a handful of others — and assigns each one a pre-established time value (in Time Measurement Units, TMU, where 1 TMU = 0.00001 hour = 0.0006 min) that depends only on the motion’s classified characteristics: the distance moved, the type of grasp or the difficulty of positioning, and so on, never on who performs it. A normal time for a whole task is then built up by looking up and summing the TMU values for its constituent motions, without ever timing or rating a live operator on that specific job.
MTM was developed in the 1940s by H.B. Maynard, G.J. Stegemerten and J.L. Schwab at Westinghouse Electric, from frame-by-frame motion-picture analysis of many skilled operators performing a wide range of industrial tasks. By measuring, from the film, how long each class of motion actually took across a large, independent sample of experienced workers, the developers derived time values that represent an objective, statistically averaged “normal” pace for each motion type — the performance-rating judgement is effectively built into the tables once, by the original film study, rather than re-made subjectively by every analyst on every future job.
MOST is a second-generation predetermined time system, also developed by the Maynard organization, that simplifies MTM by recognizing that most manual work is built from a small number of recurring activity sequences rather than an arbitrary chain of individual motions. Instead of looking up reach/move/grasp/position separately, MOST classifies the whole action into one of a few standard sequence models — principally General Move (an object moved freely through the air), Controlled Move (an object moved while remaining in contact with a surface or fixture, e.g. sliding, turning a crank), and Tool Use (a hand tool or equipment operated, such as fastening, cutting or gauging) — each represented by a fixed sequence of parameters (e.g. Action Distance, Body Motion, Gain Control, Placement for General Move) to which the analyst assigns an index value from a short reference table. Multiplying the sum of index values by a fixed constant (10 TMU per index point) gives the time directly, without the element-by-element lookup MTM requires. The result is a system that is far faster to apply than MTM — MOST studies typically take a fraction of the analyst time MTM would — at some cost in precision, which is generally acceptable because MOST is aimed at longer, less repetitive-cycle work where MTM’s fine motion-level detail is not needed.
“Rating creep” toward looseness happens because performance rating is a repeated subjective judgement: an analyst who rates leniently today has no independent check on that judgement, and successive analysts (or the same analyst over years of practice) can drift toward ever more generous ratings without anyone noticing until standards across the plant have become systematically loose. Predetermined motion-time data such as MTM and MOST break this feedback loop because the time value for each fundamental motion is fixed once, from the original large-sample film study, and never re-judged by the analyst applying it on a new job — two different analysts studying the same task with the same PMTS table must arrive at the same normal time, because there is no rating step left for personal judgement to enter. Because the values are external, published and shared across companies using the same system, a plant that adopts MTM or MOST removes the single largest source of standard-to-standard inconsistency and cannot “drift” the way a purely stopwatch-and-rating shop can — any apparent looseness must instead be a genuine method change, which is precisely the trigger the standards-maintenance program of Question 4(iii) is designed to catch.
