23-Ind-A2 Analysis and Design of Work · December 2013
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
National Exams — December 2013 — 98-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. The source prints Question 3's second and third sub-parts both labelled “(iii)” (a typesetting slip); they are answered here in the marking-scheme order (i)/(ii)/(iii), 8/6/6 marks.
Reference texts: Niebel & Freivalds, Niebel’s Methods, Standards, and Work Design (13th ed.) — operations analysis, workplace/tool design and motion economy, stopwatch time study, performance rating and allowances, predetermined time systems (MTM/MOST), work sampling, wage-incentive and job-evaluation 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.
Good working conditions are not a welfare add-on separate from methods work; they are one of the nine standard approaches to operation analysis (Question 1(i)) and, because the methods analyst is the person who studies and redesigns the workstation in detail, that analyst is also the person best positioned to notice and correct poor lighting, temperature, noise, ventilation or housekeeping at the point where the work is actually performed. Leaving working conditions to a separate facilities function, disconnected from the method being installed, routinely produces a “good method” executed at a station that undermines it. There is also a direct professional and legal obligation: Canadian occupational health-and-safety legislation (provincial OH&S Acts, CSA/CCOHS guidance, WHMIS for chemical exposures) places a duty on the employer — exercised in practice through supervisors and the engineers who design the workstation — to provide conditions that do not expose the worker to unreasonable risk, so the methods analyst who designs a station without regard to these conditions is not meeting that duty.
Working conditions do appreciably affect output, through several well-documented channels: fatigue accumulates faster in poor heat, noise or lighting, directly lengthening the standard time via the fatigue allowance; error and accident rates rise with poor illumination, awkward postures forced by cramped layouts, and excessive noise masking warning signals; and absenteeism and turnover rise when conditions are unpleasant, imposing hidden retraining and quality costs. The Hawthorne studies are frequently (and only partly correctly) cited here: they showed that output rose when lighting was changed in either direction, revealing that attention and social factors also drive output independent of the physical stimulus — but they did not show that physical conditions are irrelevant, only that the relationship between conditions and output is not purely mechanical, so both objective improvement of conditions and management’s visible attention to workers should be part of the response.
Applied specifically to tool and equipment design, motion economy asks three questions of every tool at the station: can the tool be eliminated or combined with another so a change-of-tool motion disappears; can the tool’s use be transferred from the hands (which are precise but slow and easily fatigued) to a foot pedal, jig, fixture, or powered mechanism; and does the tool’s shape, weight and balance let the hand grasp and use it with the least possible exertion and the shortest possible motion path. In practice this means: combination tools instead of single-purpose tools used in sequence; spring-return or gravity-return tool holders that pre-position the tool for the next grasp; counterbalanced suspension of heavy powered tools so the operator supplies guidance force only, not the tool’s full weight; handle contours that spread grip pressure and avoid sharp edges that concentrate local pressure (a source of both fatigue and repetitive-strain injury); quick-acting clamps and cam-locks in place of screw clamps wherever cycle time is at a premium; and control layouts (levers, triggers, dials) placed for the shortest reach from the operator’s normal working position, consistent with the reach envelope discussed in Question 1(iii).
Fatigue has physical and psychological components, and both must be accounted for when setting a fatigue allowance. The major factors are: (1) physical/muscular effort demanded by the task — force exerted, load carried, and the proportion of the cycle spent in static muscular exertion (holding rather than moving) is disproportionately fatiguing; (2) working posture — standing versus sitting, reach above shoulder height or below knee height, and twisted or bent trunk postures all raise the metabolic and musculoskeletal cost of a given task; (3) environmental conditions — heat and humidity (impairing the body’s ability to dissipate metabolic heat), noise, poor lighting and inadequate ventilation all add to the physiological load independent of the task itself; (4) monotony and repetitiveness — highly repetitive, low-variety cycles produce mental/psychological fatigue (boredom, reduced attention) even when the physical load is light; (5) work-rest scheduling — the absence of adequately timed rest pauses lets fatigue accumulate across the shift rather than dissipate; and (6) individual factors — general health, nutrition, sleep and physical conditioning govern how quickly a given worker fatigues under an identical task. Personal, fatigue and delay allowances (Question 4(i)) are the time-study mechanism used to convert these qualitative factors into an added percentage of normal time.
