### Time

```IE 327
Introduction to Work Design
Dr. Andris Freivalds
Class #19
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1
Ch. 9 – Time Study
• “Technique for recording times and rates
of working for specific job elements using
a stopwatch”
• Result → Standard Time
• “Time achieved by a qualified worker,
without exertion, using correct methods,
over an 8-hr day”
• Used for production quotas, wage
incentives, costing, etc.
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2
Time Study Equipment
1) Stop watch – decimal minutes
•
•
Analog – outdated, costly
Electronic
 A = start/stop
 A & B = reset
 C = Mode
• Split = continuous
• Lap = snapback
2) Time study board
•
•
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holds time study form & watch
L- and R- handed
3
3)Time Study Form
• Special form
• Special recording
• Later analysis
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4
Time Study Form (Close up)
(Rating)
R
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(Watch
Time)
W
(Observed
Time)
OT
(Normal
Time)
NT
5
Time Study Procedures - 1
1) Select job to be studied
•
•
•
Incentive scheme
Excessive costs
Compare jobs
2) Select operator to be studied
•
•
•
•
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Want qualified = intelligence, education,
training, without undue fatigue (fit)
Not just representative = average
Slow worker → loose times
Fast worker → tight times
6
Time Study Procedures - 2
4) Examine job – break down into elements
•
Types of elements






•
•
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A1) Repetitive = occurs every cycle
A2) Occasional = not every cycle
A3) Foreign = not necessary part of job
B1) Machine = time fixed
B2) Manual = depends on worker, rate
C) Constant (vs. variable)
Use sight and sound for breakpoints
Relatively fine but > 0.04 min
7
Time Study Procedures – 3a
5) Number of cycles - sample size determination
• Statistical estimation n = (tσ/kµ)2
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8
Time Study Procedures – 3b
5) Number of cycles - sample size determination
•
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Approximation
Cycle time (min)
# Cycles
0.10-0.25
200
0.25-0.50
0.50-1.0
100
60
1-2
2-5
>5
30
15
10
9
Time Study Procedures – 4
6) Measure (at job)
• Continuous timing
R
W OT NT
R
W OT NT
 Stopwatch never reset
 Record cumulative times
 Need to subtract times
• Snap back timing
 Stopwatch reset each time
 Read direct times from zero
• Record 2 digits, no decimal
point
7) Compile (in office) – 3 digits
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10
SUMMARY
OF TIME
STUDY
NT=OTxR
ST=NT(1+A)
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11
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12
QuikTS & DesignTools
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13
```